zeetes, you are brave to reveal this. I honestly thought it was about your friend not yourself.
The main thing I think to remember is that none of this is anything to be ashamed about. It's a chemical imbalance, a physical issue. That's why (again my own limited understanding) the meds are necessary. The other stuff I think, support groups, mental exercises, seeing a therapist and so on, are more like ways to cope daily when the meds aren't enough.
As I remind myself just about everyday, it's not what happens to you but how you react to it. Just being aware of that can keep you from making destructive choices that lead you into the downward spiral. For me, it was falling into an up all night/sleep all day cycle and then booze on top of that.
It may be different for you, but it's important to break whatever habits you have that contribute to you not taking care of yourself, mind, body and spirit. and often taking care of your body (again, sunlight, diet, exercise, etc) is enough to get the mind to follow.
What really sucks is there aren't easy answers. It's a lot of hard work and self examination and asking yourself the tough questions. The people that say a pill will fix everything are full of crap. The meds will help even you out but ultimately the only thing that will help you "fix" anything is your own will to do something about it.
and I know that's easy to say, not so easy to do - especially when you're in the depths of it. The trick is to get some upward momentum going so the downs aren't so down, and so you learn to recognize the things that trigger the downs so you can head them off before things get too bad.
My experiences are again pretty mild compared to your own, but dealing with my sister and talking to my mother-in-law, who has become sort of my mental health mentor at this point (probably no coincidence I married into a family of therapists, LOL) hopefully there is something worth thinking about.