Oh, boy. I had been diagnosed with bipolar II and obsessive-compulsive disorder with dissociative symptoms, but my bipolar diagnosis is currently being evaluated, and my doctors are considering changing my diagnosis to dysthymic disorder (and attributing the "manic" episodes to my OCD). When I was 12, I had my first depressive episode, which began my descent into mental illness until I sought treatment when I turned 19 (due to my first obsessive-compulsive "break" where I didn't sleep for a week, among other things). Anyway, I made the mistake of going to my primary physician for help, who gave me Zoloft. One of the worst things you can do for a bipolar patient is give them an antidepressant without a mood stabilizer (it will send them into a deep depressive episode, or a severe manic episode). I became terribly suicidal while on Zoloft and I really thought that that would be the end for me. I had been severely depressed for years, but this was a completely different and new feeling for me.
One night, I came across Justin Furstenfeld's video on FRND.tv (it's available on YouTube in two parts) about his struggle with bipolar disorder, and his mission to raise awareness. I know that this sounds dramatic, but he saved my life. I looked more into his music (he's the lead singer of Blue October), and found that most of his music was written about his life with bipolar, and it felt like he had a chunk of my soul, and he wrote things that I thought only I felt... After that night, I was still severely depressed because of the medication, but I felt hopeful and inspired, and I went back to the doctor the following week.
(I'm going to continue this in another comment)
Well... I can't write much more due to HP rules, but long, long, long story short, there is hope. You are NOT alone. Feel free to shoot me an e-mail or something if you need to talk or have any questions. Much love.