Sorry to hear it, man. Been coping with fucked-up bouts of depression since I was 12, so I've got nearly 30 years of on-again, off-again bullshit under my belt for feeling fucked in the head. I bought my first gun with the thought I might use it on myself (fortunately, I decided to take my frustrations out at the shooting range instead) and one night, I drank a full bottle of Black Label and took about 20 Valium just to see if I'd make it through the night. Worst fucking feeling ever, after I didn't succeed at taking myself out, I started to turn that shit around. But, it's not easy, that's for sure. What helped me was:
1. Don't sit around doing nothing. Your mind can easily be your worst enemy, and the less you do, the more it will fuck you up. Stay busy, even if it's just skating or doing stupid shit, anything is better than letting you mind take you to shitty places and feeling terrible. If you don't have a job, GET ONE even if it isn't fun. If you still have too much time, get a temp job on top of what you already do, stay busy, make some more cash and treat yourself later on with the savings.
2. Ever had something you wanted to do but never got up the courage or were too lazy to do it? There's no better time than now. Go off your usual course - take a road trip somewhere new, try your hand at something you've always been interested in but never got around to. Change is good when you feel like shit, it will do you good.
3. It sounds lame to some people, but try getting in the gym and lifting weights. I don't get to skate much these days due to being old, working long hours, and having shitty knees and no more pop, so the gym is my surrogate skatepark. I used to think it was some jockish meathead shit, but it does the body and mind a lot of good, especially when you feel shitty and need to de-stress.
4. It's not for everyone, and I feel lame for saying it, but weed helps me a lot. I'm also OCD and high-strung, and my mind goes nuts at night if I don't smoke, at least on most nights. For some people, it makes things worse, but for me, it has calmed me down enough to keep me out of a LOT of trouble, and I don't sit in bed staring at the ceiling until 6 AM any longer. Though, I don't smoke until my workday is done, I reserve that as my reward for handling my business, smoking before midnight only makes me do nothing so I avoid it until all tasks are complete.
5. This one sounds weird, but it may be a factor - get your Vitamin D levels checked by your doc. Two years ago, mine went rock-bottom, my depression came back so strong, I thought I was losing my mind and almost self-checked into the hospital for my own safety. My doc ran blood work when I went to her to consider going back on antidepressants, she found my D levels to be so bad, they were almost non-existant, she put me on a high-dose D supplement, and I felt 80% better in just 2 weeks. Never hurts to check that shit.
6. If you hang out with negative people, get them out of your life for a while. Doesn't matter who they are, they won't help when you feel bad, so hang with positive people and ditch the assholes at least for a while. Even if it means avoiding good friends for a bit, you gotta do what you gotta do. Same goes for negative situations - if you can get out of them ASAP, do it. If you can't get out of them, change things up to try and make them better. Whatever it takes, but don't stay it a pile of shit longer than you have to, it only brings you down.
I could go on and on about this shit, but this is a good start. If I can help with anything else, send me a pm or post back here, even if I don't know you, I'm down to help however I can. I may be an asshole, but I'm the good kind of asshole, and been through enough shit to have some good advice when people can use it.