What would you think of a person who goes running back to a person who left them?

This is pertaining to my mother who has failed in parenting me. If anything, people at school have done a better job at raising me and my father shows love. Anyway, my mom wants to go back with my step dad who ually abused my younger sister and I eventually drove him out of the house with all the drama I was creating because I was upset. So one day(and this happened twice mind you), he left the house while my mom was at work and everyone was out of the house and he left to a differerent country without saying goodbye to his son or anything. So I was like "Well, there's another nasty thing he did". At first she was furious and I thought it was finally over and I was free too, we all were. But then he starts calling her saying how he was buying a house in that new country for them and he wanted her to move down there with him. She said yes, she really did. And I yelled and argued and fought and she shouted me down and she called me an "evil piece of shyt" and I was the reason why my stepdad fled. Whatever. He also lies alot, especially about getting jobs and buying new things. So when I leave New York in like a year,(since I'm getting ready), I'm gonna ket her stew in her own juices and good riddance. What do you think about this whole thing?