I am also a loner, and it is curious because opportunities are always given to me but I never know how to take advantage of them, I have had best friends and people that I consider friends at some point in my life, however, I am the worst at maintaining social relationships (I no longer I have friends), I don't know how to maintain a friendship, I don't like hanging out with them unless I consider it necessary, it's very strange because I appreciate them anyway, on the other hand, I don't know what happened to me but socially I can no longer meet anyone, when I talk to someone I don't know how to hold a conversation (I can't make new friends).
As for girlfriends, I've never had one and I've never had sex (I'm 21), I've given up on the idea of having one, mostly because I don't see the point of having one, I'm aware of how boring and even weird I am. If it's for sex or whatever, I can get a prostitute, that doesn't worry me much, if not the fact of having someone's support/affection, however, I know how unrealistic that is for someone like me who deep down doesn't loves and hates commitments to people, and the idea that in a relationship I have to give a part of myself to make it work I think it makes me sick and I couldn't stand it in the long run, I guess we can't have everything we want...