I found this article intriguing, especially the following excerpt (emphasis added):
Now you’re probably wondering why people would purposely seek out the very thing they fear the most. It is a very perplexing question indeed. Simply put, I think people tend to gravitate toward people and situations they already know how to handle. Granted, these are certainly not pleasant, but familiarity goes a long way. Some victims of domestic violence seem to be drawn to familiar and yet devastating scenarios as well. Nobody enjoys getting beat up, emotionally or physically, but the fear of the unfamiliar is much stronger, and therefore has a paralytic power. I doubt any of us consciously thinks about these choices as we make them.