My thought behind that is he used to be a good person and then something happened. For some reason he now takes his pain out on her a little at a time, getting worse as time goes on. At times, we don't want to see people as they truly are but how we remember them. It can be a very painful experience.

Of course, this is a freewrite and not much editing was done. It may work later on or it may not as this story continues to develop day by day.