I've added your questions in so I can hopefully cover them all:
How old is your DS out of interest? You say that he’s now old enough to be shocked at her behaviour… what behaviour has he seen? How does he refer to her? By name or a variation of a nana nickname?
He is 10. She basically had a child like tantrum (pretending to be joking but actually wasn't) when she didn't get her own way. My son basically said 'geez Granny, calm down you sound like a child!' I was bursting with pride for my little man in being so astute as to spot the strange behaviour and call it out. She does this thing where she talks in a whiny child voice to get what she wants and says she's just joking but it's so obvious she isn't and is just trying it on. My DH hates this behaviour and has snapped at her a few times. It's just weird.
She used to have a variation of the nanny name but I'm dialing that back to just her name now. My ex SIL did the same thing over time.
Is the golden child her own daughter? Does her own daughter have children of her own?
Her daughter is definitely the golden child but it's my sibling who is currently using her to do jobs for them that I'm potentially expecting a text from. But they should know me well enough to know that emotional blackmail absolutely has the guaranteed opposite effect on me. It makes me really angry and never works.
Her daughter doesn't have children and I think this is part of the problem. She was desperate to be a grandparent.
You seem to think that this is going to escalate? What are you afraid of in this regard? More ranty text messages or something worse?
Good question. Honestly I don't know. I have a lot of unresolved issues from my childhood around how these two have behaved, so I'm on fight or flight mode at the moment. I'm thinking long emails or phones calls. My DH has already said if it's phonecalls he'll jump on the call with me as they're always better behaved when he's around strangely.
Have you had a frank conversation with you father about her overstepping and her unrealistic expectations of your relationship with her?
I spent 3 hours talking to my dad about how I felt about her and he nodded and agreed with me. He even said he regretted marrying her and didn't realise what she was like until it was too late. So he absolutely knows how I feel but goes straight back to gaslighting me and throwing me under the bus.
Sorry you’re going through this btw but your posts do read as though you’re strong and sensible enough to handle this woman and maintain your boundaries with her.
Thank you for saying this.
I guess if I'm really honest, I know she's going to go ultra controlling as dad gets worse and when he dies the funeral and probate will be just awful. I'm an executor along with her and I know she'll be a nightmare to deal with. I'm dreading it.
DH and I have already discussed me getting counselling to help me through this when it happens and I know he'll be 100% by my side.