Excellent discussion everyone. Yes, the Navy sucks, but in it's suckyness [word?], it builds character. Is it fair? What's fair? I tell my poor children that "fair" is a place with a merry-go-round and a tilt-a-whirl. The Navy's not fair. Life's not fair. The state fair's a fair, but it doesn't hold a candle to a good amusement park.
Let's talk about the problem itself. Now bear in mind that I'm a Nuclear Engineer, and not a psychologist, but let's be honest, unless you're a very special person, or truly sick in the head, or a Grade "A" A##@ole, or a zen master, then you're going to experience a fair share of depression in the Navy. It tends to be a very negative environment, especially on a carrier. So, if you will, let me share some wisdom [or pseudo-wisdom]. Who knows? Some of it might help.
Now depression is just rage without enthusiasm. That doesn't really help, because rage [jusified or not] will get you into trouble a lot faster in the Navy than depression will.
So what will help? How about some reading. You're in the Navy. You don't have anything better to do with your spare time. So read. To depressed [as well as suicidal] people, I always recommend "The Myth of Sisyphus" by Albert Camus. Don't worry, unlike most existential writers (e.g., Sartre and Heidegger), Camus is easy enough reading that it won't make you even more depressed. In it, Camus points out that the only really important decision in life is whether or not to kill yourself [All other decisions are temporary]. He explores rage, motivation, and depression. It's a good read.
Next, I'd recommend "The Teachings of Don Juan: A Yaqui Way of Knowledge" by Castaneda. Don't worry, you don't have to believe the stuff, but it is some good reading on life, death, fear, and motivation." I've recommended it to a lot of depressed people and it seems to cheer them up.
Next, let's talk activities. There's no better way to fight depression than physical activity.
I'll start out with what seems like a non-activity, "sleep." I had a good friend on the Enterprise who said that every hour asleep is an hour less at sea. He went through a period during which, any time he had any free time he'd sleep it away. It seemed to work for him. It was like he was a caterpillar turning into a butterfly.
If you get bored with that, then, on a carrier, you should have a weight room [we did]. Go pump some iron until your muscles ache. You're not doing this to become Arnold. You're not doing it to pick up chicks. You're not doing this to compete with Zugg the weight lifter. You're doing it because people feel better when they get some exhausting physical activity [and no I don't mean working on a plant component for fourteen hours only to have some Khak tell you how much you suck after you get done]. I mean brutal physical effort for no reason at all. It doesn't matter how much weight you lift, as long as you wear yourself out. Try it.
Along those lines, I'm a big fan of eastern activities (e.g., Yoga, Tia Chi, Karate, Judo, Kendo, etc.) for physical and mental well being. When I was on the Enterprise, we had some PO2 from the MAA who held Hopkido classes. I never went [primarilly because he was a Grade A jacka##], but in hindsight it would've been a wonderful way to serve time. If you don't have any classes on board, then maybe just get a book on yoga. It'll suprise you how well it works.
Also, the advice about vitamans is good stuff. I take healthy doses of A, B-Complex, C, D, E, Potassium, Magnesium, and Calcium on a daily basis, and I feel like a million bucks. I wish I'd started earlier in life.
Finally, I'd like to say please don't feel like you're locked in just because you've started down this path. Sometimes we feel like, just because we've started something, we have to finish it, even when that's getting a medical discharge for depression. You can pull out of this, one little step at a time. If you do, then let it happen. Don't get hung up just because you want to complete something.
Good Luck,
MGM