Why do I post here?
Because I have found friends and understanding that I have never ever encountered in real life. Because I don't "do" real life friends very well which makes this a perfect environment for me.

What is your definition of supportive?
Sometimes, simply replies to a thread show support. Even if it is just to say, "I can't give advice, but I do understand". I do feel that criticism, even constructive, sometimes just isn't at home in a thread where support is sought after. There is so much more to "supportive" though - what I have said here doesn't even begin to cover it.

Why do you think others post here?
I would think that others post for very much the same reasons we all do!