I'm glad your vacation went well enough. Yeah, I get the "don't touch me" stuff, too.
There's a book called something like "The Five Love Languages" where he outlines how people accept love generally falls into one of 5 categories - sex being one of them.
There are a lot of marriages where there's very little sex but the higher desire person doesn't seem to mind because that isn't his love language and he's getting his love some other way. I dare say that many on this board receive our love through sex. That's why it means so much to us. WITHOUT IT WE DON'T FEEL LOVED. I think that's why it hurts so much and we/I obsess about it so much.
Masturbating only goes so far. It lacks the touch.
I think that's the "why." But I still haven't figured out how to cope.