QueenAccountant, I hate the racing thoughts as well. For me that's a sign my meds aren't doing what their supposed to be doing, so I would suggest seeing your Pdoc (if you haven't already).

When I start to cycle through my past mistakes or the crap that happened in my past I say "STOP" in my mind and try to look objectively at what I'm thinking about. Seeing a psychologist helps with that.

I can relate to the feeling you got from your mom that it was never good enough, but try not to pick up where she left off. I know it's hard and I struggle with continuing the abuse that I received as a kid. I hope you get some peace.