I've had OCD since I was eleven and the intensity has come and gone and come again over the years.  Not something I generally tell people (in person) and I manage to keep it hidden pretty well.  It's a fucking pain in the ass, though, because I'm always stressing over it with just about everything I do and I feel like my mind can never be at ease.  It's weird because I can remember the day it actually started and it just seemed to come out of the blue.
I used to have bouts of depression, but I'm not sure if it was more from external sources or internal.  Used to have suicidal thoughts a lot, but I don't anymore.  I know there are some people who would be upset if I did something like that and it's thinking about how they'd feel that puts a stop to those thoughts.
I kinda just deal with the crap and get on with my life and try to block shit out.  The depression kind of turned to numbness and I have lost a shitload of interest in things I used to love. Seems like I put on about 90 pounds since that change, too.  All I can do is the best I can with the hand I've been dealt.  I try not to lose hope that some day things will eventually get better.