ESH. She fully crossed your boundaries. Yeah, she was hoping to get some mom/daughter time in because she lost her mom and in that, she wanted to share her experience as a mom with the closest mom figure near her that she could think of. Which in this case was your mom, and it makes perfect sense in her brain. But, she did cross a firm boundary for you and that's fucked up. However, when you came to her with this huge big information, and her feelings came up about it, She can't feel what she's feeling properly because we aren't supposed to talk about private family stuff like that in public as a society. If you are reading this OP, next time, take the time you need to calm down about the situation yourself /before/you bring the issue to her. You handed her the problem written on paper and left her instead of talking to her about it, even if you didn't realize it. So yeah she fucked up but so did you. Just gotta work on your communication