@Pandypuff
I really appreciate your expressions - believe me, I know too well how difficult it can be with certain family members...
I think the difference is that with ex partners, we've walked away, and we don't have to see them again, ever. But with family members, we're tied to them indefinitely, and every time we see each other, we get stung, again and again. That's why the hurt is so raw, because those cutting quips, remarks, criticisms, chides, are constant. And nothing we say or do seems to change their behaviour...
The only thing I can suggest is mentally accept that whenever you're with your mother, she will likely say or do something upsetting to you - but try hard not to retaliate and argue, because that will only make things spiral downhill. Instead, acknowledge that you'll never see eye to eye, and if appropriate just change the subject to something positive.
As Philippians 11:8 says: "...whatever things are true, whatever things are of serious concern, whatever things are righteous, whatever things are chaste, whatever things are lovable, whatever things are well-spoken-of, whatever things are virtuous, and whatever things are praiseworthy, continue considering these things."