Just a Thought

You know how people say that artists suffer for their work? I don't always understand that, but writers-we suffer for our work. But its not because of the writing itself(always), I think it's the other way around. We write because we've suffered. Somehow, it gives us what we need to write convincing truths. It makes the pain of our characters seem much more believable. Of course, it's not like we have to get shot to imagine the pain for a character or anything. But isn't it easier to base fiction in truth? Don't the best characters reflect part of the author and his/her experiences?
I wondering where people stand on the case. The people I give my work to to read are always saying they're trying to find me in my characters. They can, of course. So I'm thinking about how deep the psychology of it all goes. How much is fact, and how much is fiction?