I had a friend my senior year who committed suicide, he was a junior, it was very sad, and I still think about him often.  My boyfriend lost his best friend last March, and I know he thinks about him every day.
I have depression and have been dealing with it since about my junior year of highschool, it's rough, and it got so bad around that time I decided to get help that often I contemplating going to sleep and never waking up again.  I've had a lot of support from my parents and friends (depression runs in my family - thanks a lot genetics) and I'm doing great now, getting good grades, going skiing, trying to get another job.  Although, I had a very rough time three summers ago now my best friend was shot and killed by his own father (fucker was crazy, he's in jail now, forever, I hope someone rapes him anally and then stabs him to death - they got into a fight) and watching him be burried was one of the hardest things I've gone through.
RIP To those I've known, loved, and lost.