Thinking back on it, I've never done a Mary Sue. Even the characters I invent for video games are notably unlike me, and my fictions generally focus on the allistic.

There are very few characters I could inhabit in that way. I am autistic and kind of an oddball. The nearest fictional character to me would probably be Cole from Dragon Age, and I've never written anything for him.

I suppose I could. A fluffy odd couple romance between him and Dagna perhaps. Caught between Fade and Stone... he could be drawn to her because of her family woes and try to help (with hilarious consequences), and then he fascinates her because magic, and- Nobody copy this! *Frantically takes notes*

Part of fan fiction is learning to write. And part of writing, for me, is learning how to write like people unlike myself. Other genders, other orientations, other psychologies, other religions and philosophies. This, in turn, makes me a more functioning individual socially, so I suppose fic writing is a kind of therapy, in some ways.