When you are really in love with someone and it's not just shallow lust or infatuation, you can forgive almost anything.
People shouldn't feel they have to date/marry someone they are not attracted to just because society/family dictates it or they will be miserable. It's not their life or body so they have no say in the matter whatsoever.
If I was with Yuri, and I really love her and she did that to me but came back later, I would forgive her and take her back. Love isn't some easily discarded emotion that you can dismiss all the memories feelings you shared.