No it's not realistic at all, obviously, this is a movie and it's designed to entertain. There is certain things you just don't say in a heated argumment like that. But it goes to show that resentment builds up if you are sacrificing your potential and what you could have been, have a second rate-life with your wife and she in turn ends up resenting you rather than respecting the sacrifices you made to make the relationship work. In a sense, conceptually guys do all the hard work and sacrificing and women just complain and nag and jump ship when another guy who is not sick of her or knows her ugly side starts off with her while you are left high and dry.
Technically my marriage would appear to have ended on an altercation, but I didn't express those types of feelings about her to her face. We haven't been together that long to build up that level of resentment. However, the circumstances in which the marriage came apart or lead to divorce were so asinine that it did piss me off with her at the moment, and perhaps I was more passive-aggressive with the way I chose to express any quarrel (ie write-ups on legal papers, facebook posts, etc....). Sometimes a good heated arguement like that is the best because it's private and they are not making a spectical of themselves. However, even so, words said can't be unsaid or taken back and a wrong word in a wrong tone can just lead to things coming to an end.
As a movie their acting is good, but lets face it, both these actors / actress are millionaires and well-off and people who have money don't get into arguments like that. It's usually when things get tight and arrangements behind the premise of the marriage become he said she said and there are disagreements all over the place is when things really come apart fast.