Wow.. I'm at a loss for words, here.

Perhaps your mom no longer should be your "go-to" support, as she clearly doesn't understand much at all. I suspect you've been trying to get her to understand, hence the conversation, and she hasn't budged?

I'd distance myself from her and focus on your healing without her. It's possible she's at the root of your anxiety, depression, and need for alcohol. It's not a maternal thing to tell your child it was their "fault" for being raped. There's something going on with mom that has nothing to do with you.

Sorry for the trauma you endured, all around!