From what I've seen, I think everyone has their own reasons for coming here - there are some common threads, but it really differs.
For me, I think about suicide a lot, and it's nice to talk to others openly about it. In that sense, it's actually 'healthy' for me, since I don't have to bottle up my thoughts. In day to day life, it's not really possible to talk about it. (And good, because it's not like I want the people in my life to be preoccupied with suicidal thoughts themselves.)
It's also helpful to hear about people's knowledge about and experience with different methods, so that I can make a more informed choice about my own. It's a huge decision, and one that each person will hopefully only have to make once.