I can never keep a conversation too. Even online, it's sometimes difficult. I'm very lonely too, although I'm younger than you. I like being asexual.

What language do you speak? Just curious.

>I have geek humour

Perhaps you should go to some geeky places (comic book stores, computer stores) and talk to the people there. They may understand you better! Another thing to do is to tell the people you talk to that you often have trouble speaking and thinking of things to say.