I can...sort of relate. At least to the bit about food and mood. I often have serious, terrible stomach problems. To the point where many days, I was sick after every single meal. This has taken me from a person who attended university, had a social life, was relatively popular, and got out of the house every single day, to someone who leaves the house once a week if I'm lucky. When you can't see at all, how can you find a place to quietly throw up after a dinner with friends, when you're not at your own home? When things started going wrong, I spent a lot of time on team talk, or hey tel, staying social. I kept up with all of my other friends on MSN, Skype, and Facebook. But as I continued to become more and more isolated, and kept having trouble finding things I could eat, my energy level started dropping. I stopped returning friends phone calls. I never bothered opening hey tel or skype. I got off of MSN and Twitter completely. I interacted with people to the absolute minimum required to keep up with my various contractual responsibilities. After a few absolutely miserable experiences of being sick, dizzy, disoriented, and throwing up in the street, and having to get myself home on the bus never the less, I began to have panic attacks whenever I had to leave the house for any reason, and just the thought of going out would start to make me feel sick, even if I hadn't eaten. After months and months of this, I finally got a test that found the foods I was intolerant to. Of course, Canadian health care didn't cover it. I am so, so lucky that in spite of everything, I had enough money coming in that I could afford to pay for the test out of my own pocket. If that hadn't been the case, I am convinced that I would have slid into clinical depression, malnutrition, and eventual death. But once I started to get some data on the foods that were effecting me so deeply, things started to turn around. Don't get me wrong: I can't afford a nutritionist, so I'm learning as I go, and still struggling pretty hard. But I guess my point is that the downturn was all started by dietary problems, and is being fixed by dietary changes. So I don't think it's possible to overestimate the effect of food and nutrition on your mental health.
But I realize diet is probably not the be all and end all for most of you that it is for me. So, here are a few tips about how to get things done when you have no energy, no motivation, feel like complete shit, and yet have to do things anyway. These are all things that help me, your mileage may very:
1. Find low-energy social interaction. Humans are social creatures, and to be happy and healthy, we need interactions with other humans, at least sometimes. Unfortunately, face to face social interaction is insanely high energy. But what most people don't seem to grasp, is that many forms of online interaction are just as, if not even more, draining than interacting in person! Twitter, IRC, Facebook, Skype, Hey Tel, and Team Talk are horrible this way. If someone sends you a dm on twitter, for example, they expect you to respond right away, they expect you to say something clever in 140 characters, and they expect you to not snap at them if you're in a terrible mood. This kind of stress will drain you faster than if you are an iPhone with your GPS on constantly. Try moving your social contact to forums, e-mail, and mailing lists. Then, force yourself to only check the forums and e-mail at absolute most once an hour, so your little bits of social contact can be spread out through your day. On audiogames.net, for example, I get hours and hours to write my posts. I can write as long as I want. If I get tired or distracted or irritated in the middle of a thread, I can just...walk away. Nobody will question it. Or even notice, really. If I don't feel like answering a message right now, I can wait until tomorrow. Or next week. When I write a long, informative, or interesting post on a forum or mailing list, it's actually an accomplishment! I can look back at the end of the day and say to myself, hey, I did at least write those messages. They aren't fading away into the ether like a hey tel or twitter would. They'll show up on Google, and someone might even answer them years from now. When you've had a long, hard, tiring day, that little kick of accomplishment that comes from answering a question on yahoo answers or stack exchange, or writing a post on audiogames.net, or recommending a fanfic to someone on a mailing list, can be absolutely vital in convincing you to get up and do it all again tomorrow. Even if your real life wasn't wonderful, at least you were a tiny bit useful to someone, somewhere, so you don't have to mark the day off as a complete failure.
2. Journal your accomplishments. Brag about them, no matter how small, if only to yourself. I've recently signed up with an account at dreamwidth.org, because the communities there look like another form of low energy socializing, and because the journal function seems like it will be helpful in tracking accomplishments. Doesn't matter what they are, but listing them, even the tiny ones, is hugely helpful in warding off that horrible feeling that you're a failure with no motivation and are just wasting your life. I'm not sure if dreamwidth is the perfect tool or not, as I've been trying it for less than a week, so we'll see how that goes. But I do know that listing my accomplishments has helped me for years. I'm hoping doing it a bit more publicly will give me the motivation I need to actually do it, rather than just slacking off and deciding not to bother because I was sick all day and just slacked off anyway, and then going into a week long spiral of nothingness and doom.
3. Work out! Even if all that means is going on a 15 minute walk. The fresh air will lift your mood, and the activity will give you a little burst of energy. And even if you can't manage to channel that workout energy into something else constructive, working out itself is another thing you can put on the list of today's accomplishments, to encourage yourself with tomorrow morning.
4. Do what you need to do for yourself, even if it seems silly. This one is a little bit hard for me to explain, so I'll have to explain by example. After getting so sick whenever I would go out, I'd start to panic about it, and then not want to go out ever. So now, whenever I have to leave the house, I take a dramamine an hour beforehand, even though I'm not sick. Then, when I do leave the house, I can say to myself: "You've taken Dramamine, so you're not going to throw up, or feel dizzy or disoriented." Just being able to tell myself that is enough to calm my worries, and let me get on with whatever I was going out to do in the first place. Is that kind of stupid and silly? Yes, of course it is! It's as bad as a five-year-old girl with her security blanket. Rationally, I know that it isn't even doing anything; Dramamine only lasts for 8 hours, but taking a single one can keep me calm and happy for 18 hours at a stretch! Is it a good long term solution? No, of course not. I'm going to have to stop doing that once I get my diet back under control. But for now, it's a solution that will let me get on with my life, while only having to deal with one problem at a time. Accept that you're irrational, and sometimes need to do silly things to cope, and tell yourself that it's OK. I don't know what those silly things might be for you. But once you find them, embrace them, and don't judge yourself.
5. Cut back on the coffee! Notice that I didn't say quit the coffee. I tried that, and it quickly got to the point where I had a constant low grade headache, and could hardly get out of bed in the morning. But I cut the amount of coffee to 1 third of what I was drinking before. Now, I'm less angry, less anxious, less critical of myself, sleeping better, and happier. But that single cup of coffee still gives me the little boost I need to make getting up in the morning possible, and ward off the headaches.
6. Find low-impact entertainment. What I mean by that is, find something that you enjoy, that won't suck you in for hours and hours at a time. If I start a fiction audiobook, it will suck me right in, and then bang! My entire day is gone down the tubes, and there I am feeling like a lonely worthless failure again. Often, I reward myself on a Saturday with a fiction audio book in the morning, and the promise that if I don't get anything done that day, I'm not going to punish myself for it. But you do need something that will make you happy during the week, to. For me, this is nonfiction books, fanfiction, and MUDs. In general, I allow myself an hour of work, an hour of low-impact entertainment (mud/fanfic/nonfiction), an hour of work, an hour of low-impact entertainment, etc, etc, throughout the entire day. If I try to work from 9 AM to 5 PM, I'm exhausted by about 11:30 in the morning. But I find I can keep that two hour cycle up from 7 in the morning to about 11 at night with hardly any stress at all. And by work, I don't just mean things that will make money, or school work. I consider work absolutely anything that I can put on my list of accomplishments at the end of the day. In general, I find this results in me doing about 6 hours of business related quote real unquote work every day, and 2 hours of other accomplishment related work like working out or writing or whatever every day, on average. When you start to find that your entertainment breaks aren't restoring you as much as they once were, switch what you're doing with them. Recently, I spent about 2 months mudding, then switched to a month of reading Harry Potter fanfiction, a month of nonfiction books, and now I'm on My Little Pony fanfiction, but am probably going to switch back to MUDs again soon. If I don't switch it up like that, I start to find that entertainment just starts to feel like work, probably because I'm overly involved with it.
7. Accept that even if you do all of the above perfectly, and it all works for you most of the time, you're still going to have crappy days. The trick is to accept what happened and try again tomorrow. Because if you don't accept those days, you're going to fall into the nothing spiral once again, and pulling yourself back up it again gets harder and harder the longer you fall down there.
[wow]! That was super long. This is stuff I never, ever talk about. So I hope someone, sometime, can find something at least a little bit useful in that massive wall of text.