Honestly, it should be up to her to make that decision.

I lived in a bad marriage for 33 years but I wanted out from the beginning.....where there are other women who wouldn't have had problems with the guy I was married to.....but maybe they would.....but honestly, it needs to be the woman's call.....if she's satisfied with the marriage the way it is.....then let her be.....I was blatantly obvious about not being happy from the beginning which is why we had all the fights we had. You would know if she were just tolerating you & the marriage....it's quite obvious because of the ambivalent feel that exists if there isn't fighting.

Leave the leaving up to her otherwise....let her be happy with the marriage because it's not your place to tell her whether she should be happy or not