If this has been a European movie Spoiler alert!
Spoiler
If this has been a European movie he would have either left his hard faced, cold bitchy unsupported wife and followed the sexy student cause he would have had access to threesomes all the time. Or he would have just kept her on the side like many European men do, no fuss no bother.
I knew that switcheroo was coming at the end.. he HAD to follow middle class morality and go back on his cheating wife FOR THE SAKE OF THE CHILDREN!