I hope you don't mind me posting here, but a few things caught my attention and I wanted to ask about them.
You said the idea of him being with the other women is just "gross" to you. Why is that? Do you think it might in part be because they have one or both strains of Herpes? Or is it a spiritual/emotional type of thing? Sort of "If he spends time with them, it somehow dilutes or poisons what he feels for me" kind of thing? Why? What could you or he do to help dispel that feeling?
What about him having more partners makes you feel less special? Is it because he picks other partners so similar to you? If so, have you thought about asking him "What's special about me? Why did you want me and why do you want to keep me?" With Asperger's, who knows what kind of answers you might get, but it might be worth taking that step. Or do you feel less special because you had the hope of being able to spend more time with him (and Miss Pixi) when you moved and that's turning out not to be true? It sort of sounds like he's taking the extra time saved by you living close and using that to pursue other partners and that worries and perhaps offends you. You're wonderful and he has more of a chance to see you and he's not taking the chance. What the hell is wrong with him?!? Of course, I could be completely wrong, but I could see feeling that way myself.
There's nothing wrong with obsessing on the problem so to speak, as long as you are making some headway. Figure out what the specific issues are so you can make a plan to deal with them in a less icky fashion and when it gets too much, then you should definitely distract yourself. I do that all the time.
I really feel for you. Like, I saw another post and came over here to read what was going on because I was concerned. I really hope you are able to work through this. No one should have to feel that way for very long.
I'm rooting for you.