It sounds like a guilt thing. He's tormented by the fact that he's robbing her of her teenage life, or at least that's what he thinks he's doing. It doesn't help that half of the females that know and/or trying to get into his pants keep filling him with these ideas. So he's trapped between a self made rock and a moral hard place.
Both the husband and the wife have issues with communicating. He is easily swayed by words, which is how he was goaded into cheating on her as well as his current issues. While she doesn't know when to put her foot down and is way to submissive for her own good. Honestly, both need a slap and a stern talking to by someone without an ulterior motive.