The best anti-depressant is taking comfort in the things that comfort you during depression, unless it's food of course, which becomes a bad habbit. Rest, stay calm and stop dwelling on thing's you can't change. Nothing's permanent in life, and if you don't learn to let go as your problems do, life can do nothing but get worse when the next hardship comes around.
The biggest thing you need to work on is not blowing things up in your head, the fact that your depressed and descirbing others problems says your just beating yourself over problems that aren't yours to deal with. Let it all go man, concentrate on the things that make you calm/peacefull/happy.
ps: Things I do when I'm down - Sleep, lay down and watch something funny on TV alone, toss the football with a friend and just relax alot.