It's actually even contagious.. when those you know commit suicide or even celebrities - it makes it seem easier to those around you. I've been struggling for the past year, myself with major depression, and I know when Chester Benngington (Linkin Park) died, for awhile it seemed like it wouldn't be such a bad idea, myself.
I had a brand new baby though, and every time I felt full of despair, I'd go and hold him for a bit. It helped bring me out, or at least give me a reason to live a bit longer till, my mood swung in the other direction.