If your girlfriend/wife cheated on you with a girl?

[ßringer]

Why would the sex of whoever my partner cheated on me with even matter?

The genitals of the person she ****ed doesn't matter - It's the act of betrayal that does.

[El Angel]

cheating is cheating with a girl or a guy, either your penis didn't satisfy her enough that she needed to find another man or your penis was so disappointing to her that she completely gave up on men.

This. Either way, it's a severe blow to your confidence.