hidden_self, I cut and pasted your father's satement ibto a list of famous and not-so-famous quotations I maintain.I have been putting off replying to this thread because it's way too close to my own situation for me to have any real perspective on it.
I would just like to say that I think sexual differences are a fine reason to end a relationship. Not an easy reason, since it might seem like something very shallow. But sex is important.
Someone I know observes that when sex is going well, it's 10% of what makes up the relationship, but when it's going badly it's 60% of the relationship. Point is, bad or insufficient sex will become more and more important over time until the hurt and resentment and even contempt poisons the good things about the relationship.
There is another thing I'd like to share-- a piece of advice my father gave me many years ago. I sort of dismissed it at the time, but the longer I live the more true I find it.
He said, "A relationship is like a three-legged stool. The three legs are friendship, common goals, and sexual compatibility. If you've got all three, it will work. If you've only got two, you can sooooort of make it work but you'll always be struggling. Only one, forget about it."
Hope some of that is helpful.
Perhaps another analogy would be that sexual incompatibility is akin to a rot slowly prgressing up the leg of stool and then into the seat, thereby assuring eventual destruction.