Because he’s a psychopath who will keep trying to have control over you and will emotionally manipulate you and do whatever it takes to keep that control. And if he can’t have it, he will become violent.

And honestly, being someone who hates conflict and generally tries to be nice to everyone and who tries to be liked by everyone, someone like Dennis is a total threat to someone with a personality like mine. I don’t know how I would deal with someone like this.

Having dealt with a few people like him before, I have found that you really have to know your boundaries and never let people cross them. And also never let them talk down to you and insult or humiliate you. And if they turn violent, your have to walk away and ignore them.

That and the being a serial killer