Everything in this chain of comments has now been proven true in my particular case. Thank you for the advice. This bit sums it up pretty well:

Instead of simply cutting contact you can tell your parents how you want to be treated. As long as they are willing to act that way you interact with them. If they don't then you don't and you retry after half a year.

Clearly explicitly communicating your personal boundaries isn't easy but it's a very important skill. It's a challenge that provides a lot of personal growth.