Stay out of this, PLEASE. You can't win this and there are huge psychological issues in this you are completely unaware of. Please if you want YOUR future marriage to not be like your mom and dads get out of the middle of THEIR marriage. Instead watch the dynamic and learn and focus on growing up, getting an education and a career and moving out. That is your job not a pseudo rescue of your mother that is all just manipulative bullshit. Your mother is NOT helpless and your father is NOT a controlling bastard. This is their marriage and their dance and it works for them even though you do not understand nor see the sense of it. If your mother didn't like it she could change it in an instant. She lives in a free country. PLEASE stop and refocus your efforts on yourself you are not their equal, you do not have the insight to judge one right and the other wrong.