I was going to give general tips on how to maintain distance but not entirely shut off your mother after your OP, but with your follow up post about her holding grudge against a 3 year old and throwing dogs against a wall - not safe to have her around your kids. You can maintain calls and holiday cards to the extent that your have emotional bandwidth to do so, but I can't imagine allowing access to the kids beyond an annual meet up in the park given what you describe.

Op here, floored by the wisdom and kindness of these responses. I am literally going to print these out and save them for when I have those moments of uncertainty. Thanks to you all.

Anonymous wrote:
In your case, it seems far safer and healthier to remain "estranged." Give up the fantasy of an extended family for your kids because they and you deserve better and dealing with flaky, extended family members who defend your mom is still dysfunctional.

Focus the same kind of energy that you have used to build a good life with your own family and career on creating a family of friends.

I agree. OP, I am in a similar-but-different situation and sometimes question our choice to withdraw (not completely estranged, but at arm's length). My father's comeback to our "overprotectiveness" is that "you can't protect them from everything." However, I choose to protect my DD from who I am when I am around those people. Like you, I have some long-simmering childhood issues which I have fought to overcome. When I am around my family for any length of time, it all bubbles back to the surface. Sorry, I'm not going to have her grow up thinking that this is appropriate behavior, and that this is an appropriate family dynamic.

I also agree with the PP's comment about creating a family. We have great relationships with other people... some are family, some are not. It does not matter. they are positive connections for our entire family.

I have no regrets OP. As others have said we have to give up the dream and face reality. We focus on the family members who treat us well. We are modeling for our children healthy relationships and that there is NO relationship, not even family, where it is acceptable for people to be repeatedly verbally and emotionally (of course physically) abusive toward you. This isn't about accepting quirky Aunt Edna who occasionally loses her marbles, this is about repeated abuse over a long period of time where nothing you did could change the dynamic.