Establish firm boundaries and, if they're transgressed, cut off your parents. Period. Zero contact, even if they show up on your front door screaming.
For me, it was the most difficult thing I'd ever done. The benefits for you and your family though are worth fighting for and it's the only way you might have some semblance of a relationship with your parents in the future. You don't deserve that treatment.
The book Boundaries: When to Say Yes, How to Say No to Take Control of Your Life by Henry Cloud and John Townsend is what helped me work through this. It's definitely written for people who are Christians, but I've heard secular people recommend it heavily.
Finally, seek a therapist. If you're like me, you've been broken in ways you can't even identify and a professional will help you work through that.
For me, it was the most difficult thing I'd ever done. The benefits for you and your family though are worth fighting for and it's the only way you might have some semblance of a relationship with your parents in the future. You don't deserve that treatment.
The book Boundaries: When to Say Yes, How to Say No to Take Control of Your Life by Henry Cloud and John Townsend is what helped me work through this. It's definitely written for people who are Christians, but I've heard secular people recommend it heavily.
Finally, seek a therapist. If you're like me, you've been broken in ways you can't even identify and a professional will help you work through that.
Good luck