I've only ever had one romantic relationship in my life and liked one other boy previous to that. I mean, I can tell when a guy has a good body, if he's worked out and is over my own height when I wear high heels that's when I usually get a feeling from the start that the guy is ok (usually it's only later that I figure out it is because I like the way he looks). I'm not so good with faces but finally I do get it, generally in the same way with the "he is ok" feeling. I know, I'm really slow. I usually have to analyze it in a way most people don't. I think, despite what I've written below and despite all the stuff that happened, that my ex is the one person in the world that understands me the most and the one person I could ever be with.
My relationship lasted about 3 and a half years. Partly because I react very slowly and only realize, say that I'm offended by something, later than most people. Also, sometimes stuff that should, in my friends opinion's, get me angry just doesn't bother me. I believe he has some traits. I know that despite he pretends to in front of some people to be liked, he hates social situations. I take a million years to realize I have been offended but he never realizes if he offends someone so, that combination can be a problem. This ended up letting him treat me in a way that many would call disrespectful. It was difficult for me to let him know that I was angry at him. To start with because it usually happened way after the incident when I realized that I SHOULD be angry and by then he had forgotten. When I realized stuff like this we usually talked things out but one day after a minor incident, due to a combination of things I felt I really couldn't explain things at all. I got a bit desperate and just wanted him to stop bothering me. So I decided to break up with him about two years ago. I do not regret breaking up with him at the time. I was overwhelmed and had a lot built up from previous incidents that had gone unsaid because of my delayed reactions. Since he's been my only relationship I had nothing to compare it with but I know that it probably can be better than what it used to be back then.
I still wish we could get back together because in spite of all that, he really gets me. He understands when too much people freak me out because it happens to him too, he understands when I get obsessed with stuff and helps me turn that obsession into something produtive, he helps me channel my creativity and we work as one really good team for almost everything, because for everything else he KNOWS me... which doesn't really happen to me a lot. I do hope he has gotten better at identifying and giving a crap when he offends someone, especially me! I know people think we are both weird but I think that if it had been just any normal guy we would not get along as well. My friends tell me I shouldn't wait for him but I dont think I really am doing so in the way I think they mean. I just have no interest in other guys for serious relationships and know that if I didn't wish we'd get back together I still wouldn't be interested, it is a wish and I don't think it would make any difference if it were not there because of the way I am.
In conclusion I believe the only viable relationship for someone on the spectrum is with someone else in it because it's the only person that really gets them, or maybe a shrink would do too as a last option.