I've never truly been good friends with my MIL. We get on to a polite acquaintance level (I have really tried to be her friend but she's not interested) and that's it. My issue is her obsessive buying for my children. My son is 2. Recently, she's bought him a tablet and an 8ft trampoline without asking, just turned up at our house with one and got FIL to build it in our back garden. She's recently bought my baby DD her first ever swimming costume, Despite me saying I wanted to. Everytime we go to visit, DS has countless new toys, clothes and games. I can understand that perhaps she means well, but I'm never asked or told about it. And they're big expensive presents usually. For no reason. She knows my family aren't as wealthy as hers, and can't afford the kind of presents she gets the grandkids. I worry about future Christmas's, when the kids are older, and she does one of her classic buying blow outs, which my parents could never match. (Not that Xmas is about presents but kids are kids). She also knows I work really hard to make sure that my DS learns the value of gifts and toys as my parents did with me. MIL was like this with her own children and my SIL has grown up to be an adult spoilt brat. I don't want my son thinking in future" oh well mum says no to a new (X) but granny will get me one."
How do I approach the subject with her without sounding like a massive bitch?!