I'm sorry that your mom makes you feel this way. Some parents just really suck at being parents (my FIL is like this and it pisses me off how it makes my husband feel).
You are a beautiful woman and an amazing mom, and nothing your mom can say changes that! Nothing.
Man, mother daughter relationships are complex! I love my mom, she's my best friend, we talk everyday, but even she annoys me regularly, lol. Like yesterday, she insisted that I HAVE to put a nightstand in Macy's new bedroom and it totally annoyed me. I don't want a nightstand. Stop telling me to buy one. It wouldn't make sense to anyone else why it annoyed me and complaining probably sounds dumb to outsiders, but it's these little instances time and time again that mom's like to do to their daughters implying they actually know more/know what's best for their daughters even more so than daughters know for themselves.
I know this is not quite the same as your situation but believe me, I can relate to the annoyance you feel. I would imagine our mother's felt them with our grandmothers and chances are are daughters will feel them with us. I think it's in mom's DNA to step on the toes of their grown daughters from time to time. Actually, I am sure that Macy already feels annoyed by me!
But after saying that, I am sorry you had such a tough time with her when you were a teenager. That is already a tough enough time and then you had to deal with the divorce, your father's death, switching schools and moving back in with you mom. I guess the only good news from all of that is you can take you experiences and try to change those things for you kids (well, what you can control) to give them the best, stable life possible. But know, there will probably be something that your kids wished you had done differently too
((hugs)) Sounds like you need a good break from your Mama!!