Oh man. I am really sorry for you. But as the poster above me said, you know what you need to do and you just need to do it sooner than later. Take your time, but don't make it too long.
Literally this past weekend I have come to the realization that I have a history of falling for mildly autistic people (2 people so far, 4 years total time) and who have similar behavior as your guy. I need to stop doing that and look for someone where I can make it work like a relationship. There may not be as much fire in those relationships, but it is more sound.
So, be strong and do the right thing.