Plenty of people that are attractive and good (or at least non-jerks) that get broken up with. They don't necessarily have to be a jerk, just not a good match for their partner. Politics, views on marriage, mismatched libido, kids, etc.

Some studies suggest we date people of compete able attractiveness. Whoever he was dating was most likely as good looking as him and would not consider it a blessing to stay with him.

I dated someone once who was really great, did everything right, perfect on paper. However we broke up because I just didn't feel anything, there was no chemistry and sex was boring and lifeless. Sometimes that happens and its nobody's fault.

It is true for all, no matter how beautiful - someone, somewhere is tired of that person's crud.

[edit: this is true for all sexes but I guess the unkind reader will think beautiful doesn't apply to guys]