I have name changed because this is very outing and I don't tend to talk about it on mumsnet. Also a bit of back story so if you're willing, read on...
My DP and I look after his nephews. He and his brother have no other family and very sadly his brother and SIL were involved in an accident a few years ago that resulted in her death and brother being seriously injured, leaving him in hospital for nearly a year.
My DP and I were at the time planning our wedding which we obviously put on hold- and it's remained on hold- while the boys came to live with us. We bought a house near their flat. SW have been involved and were very happy with my DP and I as carers. BIL may never be able to look after them independently as he gets very tired and so we now have a nice setup where they are with us during the week and BIL at the weekend where things are more relaxed, but we all spend a lot of time together.
The boys' mum's family are all in the USA, though aren't american. She had one DSis who has met the boys twice since the eldest was a baby. She has come to us for an extended visit. She has spent the entire visit talking about how she is their "real" family and offering for them to come and live in America with her, talking about how things are so much better there etc etc. The boys have found this really unsettling and the eldest became really upset when on calling me "auntie Lego" he was told "oh she's not your REAL auntie- she's not even married to your uncle!"
Now both boys have started asking me if I am their "real" auntie, if they'll be taken away to live in America, etc.
I've found this really upsetting as well. I've known the boys their entire lives and DP and their dad have been trying to reassure them, but I just want her out of my house. But I also realise that it's important for them to have a relationship with a blood relation given how few they have left- and I have to remember that I'm not their mum (regardless of how it feels sometimes!)
WIBU to tell her that her behaviour is unacceptable and she can either change her tune and stay, or that she has to leave? Or is it not my place?