DD (7) has a friend whom she adores and wants to frequently see for playdates but who IMO is often really quite horrible to her. The friend (will call her A) is more outgoing than DD and consequently has more friends than DD who is quite introverted and can be a bit of a pushover. Over the summer holidays we've either been round to A's house or had her round ours three times, and all three times I've witnessed her being mean to my DD, telling her she doesn't want to sit next to her at lunchtime, she wants her to go away, she doesn't want to talk to her. The last two times this has been witnessed by A's mum, and if it were DD speaking that way to her friend, I would have told her off for being rude and hurtful, but A's mum doesn't do that, just says to me that A is learning to assert her boundaries and they want to support her to be able to do that and not be a people pleaser.
Any advice? DD really wants to play with A but it's getting to the point I don't really want to say yes to playdates as she just seems to spend the whole time being told to go away!