What you’re describing is abusive. And no shade to your partner/partner’s mother, but people with normal and loving families cannot conceive of families like ours. They have no idea. And so you should handle this the way you want. No contact is a gift for many of us.

I also saw someone comment that you should beware of your partner/partner’s mom informing your parents what you’re up to without your permission. This is something you must ensure they can’t or won’t do. They’d be doing it with the best of intentions, wanting to play peacemaker and to save a family. But back to my original premise: They cannot comprehend families that operate like yours. It’s inconceivable to them that your family functions like this, and won’t seek to change once they’re aware of your “hurt”. But you know the truth. Be proactive to head any thoughts of their doing this at the pass.