My friend taught me a really good trick to help with not wanting to go back.
It helped me tremendously.
When you start thinking about the nicer parts of the relationship, a good memory, counter it immediately with one of the bad memories, something terrible you experienced. This helped me to keep my thoughts balanced when I left. So, when I thought about some funny laughs we shared I also thought about his angry face slobbering and yelling when drunk. That help to give me a dose of reality when i was heading towards fantasy-land.
Stay strong, sounds like your parents really love you!