Probably being autist myself, social interactions are a nightmare for me. However, to circumvent the freeze they would cause, I either try to interact 1-1, so I have only one to interpret, or if there are more people to talk to, I" turn off" the part of my awareness that says how many people are surrounding me. Perhaps the same discipline could be applied to plain introvertion?
Also thinking negative is a downward spiral. You say you're a disappointment, but instead the lack of social interaction skills could be seen as a sign of what's to improve. Maybe consider doing a communication or theather course, or something of the sort to help?