You sound just like my son.
He took the not going out to the enth degree and didnt stir outside the door for ten years.
Finally I dragged him to the docs' and he went into therapy and is making strides back into the big bad world.
Get down to your doc now, before you find its ten years on and you're stuck.
Take something that you feel strongly about or really, really enjoy and find a group or something IRL- all they'll want to do is probably talk about the mutual interest, takes the pressure off having to start with introductions and find common ground. The more passionate you are about it the better.