Unfortunately, there may be more to it than just the fact that some violent people play football because of its physical nature. There is a documentary called The Crash Reel (it's sometimes viewable on HBO Go). The subject of the documentary was a world class snowboarder who suffered a traumatic brain injury.
There is a scene in the documentary when the snowboarder is meeting with a nuerologist. They are going over test results of a CAT scan (I think it was a CAT scan, it may have been an fMRI). In the scene, the nuerologist says he watches Sportscenter and sees the highlights at one end and then all the violent arrest reports on the other, and people think they are unrelated. They may not be. The documentary makes a compelling case that traumatic brain injuries can drastically change your personality, especially your ability to empathize, making you a less caring, often more violent person.
The nuerologist shows the snowboarder a chart with his results on it (colored areas of the brain show signs of damage). The nuerologist then shows a chart of a veteran NFL running back for a comparison. The running back (who never suffered one official traumatic brain injury, but rather multiple less-serious concussions) had way more damage done to his brain. So this would seem to mean that the hits suffered over a life of football can make someone less empathetic and more violent, even if they were always a good person otherwise.
It's very sad, and hard to think about, especially as a fan, player, or parent. This is why we need to have a better understanding of the science behind concussions as soon as possible.
Also, for what it's worth, I think it's in poor taste for the OP to take pleasure in a player on another team being abusive to a woman.