Aspergers would be my thought. They can be very., very smart, but they truly do not understand, and can't understand social norms. I had one kid who worked for me who was high functioning Aspergers and I was able to coach him in how to behave around women. What was expected in certain moments or interactions etc. He ended up marrying a nice girl and they have a couple of wonderful kids. He still doesn't understand why they need his affection but he gives them the affection as best he can.
We still talk and invariably a question will come up about how he should respond in a certain situation. He files my suggestions away and then trots them out as needed. For us it is natural, we need not think about it. For him it is like watching a computer work as he go's through the various permutations and figures out which response is the most appropriate. It has been well over two decades now so his responses are almost normal for the vast majority of his interactions. Most people would never know..
