It sounds like moving back in with your parents was a bad idea. These are not your problems. Your father told you about your mother, and now he’s expecting you to keep it to yourself. There’s no need to pretend that everything is fine. If you didn’t live there anymore, this would no longer be your problem. This is not to say that you would ignore it and act like nothing is happening but these are their problems to work through. It’s their marriage.
As for your mother no longer acting like a mother, you and your siblings are adults (from what is sounds like in your letter). The job of a parent is to prepare their children for the world, so they can make it on their own. That job usually ends around the age of 18, and then parents need to make the transition to advisor and friend. You moved out and were doing fine but decided to move back in. Your mother had moved on with her life and was doing things that interested her. The way she figured it, her job was done.
Understandably, it’s difficult to be in the middle of this type of situation. Your father should have kept that level of personal information to himself. It would have been better if he could have gone to a therapist to discuss those issues. It’s the ideal place to be dealing with matters of infidelity and other relationship issues. You might suggest that he talk to a therapist about these personal issues instead of you. Therapists are trained to know how to deal with these issues.
If you’re struggling with these issues, you might also consider consulting a therapist. It might help while you are living with your parents. It might also help you to clarify what you want to do with your own life. At 25, people are exploring what it is they want to do. They are thinking about their careers, developing their own relationships, and getting to know who it is they are and what they want to be. These are the developmental tasks that are necessary for healthy psychological growth and development. These are the kinds of things that should be the primary focus of your life at this time. Let your parents deal with their own marriage and relationship. They are going to have to figure out these things on their own.
I’m sorry you’re dealing with this problem. It’s not easy to be in the middle of these sorts of issues. Love and support your parents. Offer your moral support, but its best to try to focus on your own life. Good luck and please take care.
Dr. Kristina Randle