I hear you. I've been much more sociable in the past but now have few friends and have what I call my 'safe circle' which includes my partner, kids, parents (sometimes) and 1 friend. Even at that I rarely see the friend and prefer to stay at home. I know it's not healthy to do this all the time but until I feel different, I know I will just panic if I'm forced out to see other people.
I do find it a little easier to talk to strangers and find that it helps just to go to the shop or something and pass little comments with a neighbour or a shop assistant. Sounds a little pathetic when I see that written down but it's baby steps for me to be able to talk to anyone.
I hope things get easier for you.