How many is a few for you? Do you want to avoid interaction in person AND on the phone, or just in person? I ask because I'm a receptionist in a very small accounting office. There are only like 5 of us here, including my boss. Because of my anxiety, I sometimes have trouble interacting with people in person but I do much better on the phone.

Anyway, my point was that if you can find a small office to work in (for example, because I don't know what kind of work you do or want to do), it might not be so bad for you. I'm pretty antisocial because of my anxiety, but this is manageable for me most of the time. (At least until tax season, when traffic into our office really increases.)