Thanks @hidcat, @badbadbeans, @nightmanagerfan, @angelmiracle, @cardboard33, @squirtlesmumagain for all your kind words, validation, stories and support. I'm grateful, and it helps not feel so alone/ride this out. I'm sorry for anyone who's had to negotiate similar difficult dynamics in the past!
For those who have said - yes, she definitely has these huge gaps in self-awareness/empathy, even though her heart is in the right place. I never quite worked out what is not understanding social rules/boundaries, and what is inability to own up to her stuff because it's psychologically too challenging. End result is the same, she keeps breaking agreements/boundaries, is surprised/upset/offended when there's a reaction, and if you hold boundaries strong enough, deflects it back onto you cause she can't cope. (The last time I didn't strike the balance quite right, I had her crying on the phone for two hours about how I, as a small child, made her feel not enough as a mum because I was so sensitive/had needs. Obviously... that is not my baggage, but it's taken 30 years for me to be able to separate it out.)
She's actually a lot better nowadays than she used to be, and she does really try, and in other ways, can be very supportive. But firm boundaries seem to be only way to stabilise the relationship.
She's not responded to my text yet, and we're meant to have a family skype with my brother tomorrow who she's visiting. Nervous about it, but I've warned him so he can exit himself if he needs to and beyond that I just need to remember that holding firm doesn't make me an awful person.
Feel a bit like I've hijacked thread - hope nobody is holding the less weighty bump talk for my sake, anyone. If so please return, I'll be zero offended. Normality is good. Hope you're all having a lovely weekend; we had our local antenatal class today, which felt a bit early but super interesting!