When does one become the other? How much 'not going out' is considered noteworthy?

I can count on one hand the number of face to face friends I have... I dont leave my house unless it is for a T appt or something someone in my family needs or if they are with me too. I will not call anyone and invite them over. I dont get calls to do things either. I am now comfortable and can joke and smile at the people who work in my T's office...they all know who I am on the phone and when I come in.

HOW do I change this? I hate thinking someone will 'find out' what a loser I am.