Family Dynamics

https://www.nytimes.com/2017/09/05/style/cheating-dad-relationship-advice.html

Your father was dishonest and manipulative toward your mother. Your mother converted his cruelty into a narrative about female inadequacy, which she projected onto you and your sister. She also enlisted you as a conspirator in unearthing your father’s betrayal — rather than confronting the man herself — then held you responsible for what you discovered. Your parents were troubled people, and in their trouble they set you up to struggle with trust issues in your romantic relationships.

Those dynamics are what you need to walk away from to create a happy life; doing so will make it easier for you to forgive your parents — and to forgive yourself for needing to limit contact with them.