For me, the best way to make friends (though I admit I do not go out and socialize outside of school) has been to just talk to people in class.
As for finding a major that makes you feel at home...you just never know. I came to college with no clue what I wanted to do with my life but started out in biomedical science because my family thought I might like that kind of thing. I then switched to mathematics, where I was required to take a C programming course. I had never written a line of code in my life until that point, and I fell in love with it. I am now a junior computer science major.
Dating? I am learning about that, little by little. Before you know it, if you talk to people in your classes enough, one might ask for your number. That happened to me this semester, and I have gone on 3 dates so far with a fellow CS major who shares many interests with me, is a true gentleman, and has fantastic brown eyes. I am also scared to death that he might start trying to show physical affection, which I am REALLY uncomfortable with.
Just go with the flow (as hard as that can be for an Aspie...ha)...things you never would have imagined might just unfold.