I guess that after all, nowhere is free from the cruelty of humans and it never surprises me when people act in such a hurtful way. There is an option to vent on your profile page and set it on private so that nobody can dismiss your suffering in any way. But certainly this forum isn't exactly a supportive place, I think that this site is fine if you just want to vent and are not looking for any kind of response/support and don't care about how others view things.
That's the way that I see this site, I use it for my own benefit and I couldn't care less about what others write here, their opinions are insignificant to me and anyway your feelings and suffering are completely valid and you should take no notice of insensitive people. It really is disgusting and unnacceptable how people make those who are suicidal feel worse.