I doubt I'd be his type to be honest, a bit too on the male side to be perfect for him.
I have however been in his position. Spent 3 years in an almost completely sexless relationship with DP. I know what it's like to feel like you're stuck in an impossible position, that either you destroy something that's absolutely perfect in every other way, or go without something you need in order to be with someone, potentially for the rest of my life. And yes, it is a need for some people. I couldn't be in a relationship that didn't include sex in some form, at least not without something like ill health being involved (and yes, we've dealt with a year of that as well.)
Luckily for me, while DP didn't want to have sex, she really wanted to want to have sex, so we worked together to resolve it. And luckily for us, the resolution turned out to be really simple. Stop taking the pill, suddenly libido! Shame it took us 3 years to work it out!
I won't disagree with you that some men want variety no matter what they have at home. As I've said on other threads over the last couple of days, my Dad is the dictionary definition of that man.
That wouldn't work for me though. I'm happy to have casual sex or a one night stand, but only if I'm single. If I'm with someone, then that's the person I want to "be with". But I can't stay in a relationship with someone who doesn't want to sleep with me, any more than I could with someone who doesn't love me. Luckily DP didn't want that either, and we managed to sort it out before it came down to the wire.