i found an awesome pts book 'close to home' the first chapter is free on lifeafterwar. org
i gave antidepressants a go some time ago - twice - bad idea - it masks signs and feelings but doesn't heal the original hurts. i found breathing exercises (just breathe deeply), and acceptance of circumstances (good and bad), and prayer helpful. i did my best to eat well and sleep well, as mentioned. i also cried for three years straight till i didn't hurt so much. it's not a socially-accepted thing unfortunately, so i had to howl and bawl privately.
sorry if any of this is garbage for you; it has helped me. best wishes.
I can't speak to the PSTD, but with the depression I found the ability to function through regimented sleep/eating schedules. I forced myself to follow "sleep hygiene" (going to bed at the same time, waking up at the same time, not doing anything but sleeping in bed). I watched my food intake (high fat, high calories can exacerbate things).
Truthfully though, a brain under stress changes physiologically and antidepressants can help re-train your brain (some people do have to take it for the rest of their lives).
I would say a free health clinic is your best bet. Unfortunately (for your situation), medication and therapy have been shown to be the best way to deal with it.
You can go to free health clinic and they can give you or recommend where you can get cheap antidepressants because medication can sometimes help you just have to take them for months before you can really start feeling better. Or eat a lot more health foods because they help boost your energy and make you feel better. Also find something it can even be one thing and keep doing it- a hobby to keep your mind focused.