Going to school in person would be a start. You have to talk to people at some point.
Your isolation will just make it worse. You could also get a part time job while you go to school. You dont have to be a social butterfly. I keep my socialization to a minimum too. If you cant get over it alone you should speak to someone professional or pick up a self help book on coping mechanisms. Still having problems..Then maybe its time for St.johns wort or a scriipt med to help with the anxiety.
Everyone gets nervous meeting new people. But you have to get over it and you can because you said you can be yourself after you know someone awhile. Its not impossible. Just annoying/hard/uncomfortable.