Just stopped DD (9) attending party after being rude to me - better ways of handling it?

[Mummyinamask]

DD is currently being rude/unpleasant to us and DD1 when she is feeling annoyed for some reason (usually trivial but she is 9).

This morning after being asked to do something she said 'I was going to do that in a couple of minutes, d'er' with all the pre-teen anger and contempt she could muster (which was a surprisingly large amount considering what a bloody nice life she leads).

I saw red and promptly grounded her: no swimming this morning and no party this afternoon. She flipped and wailed and screamed and pleaded but I stood firm.

If I allow this now, she'll be at it until she leaves home (mid 30s given economic climate, so a wee while).

I'd rather not stop her going to party but nor do I want this sort of talk aimed at anyone, not me, not DH, DD2, friends, teachers . . .

So, wise MNetters;
What should I have done (something tells me there will be a next time)?

And is there anything I can do to allow her to the party while not backing down and ensuring consequences for what I consider to be unacceptable behaviour?

Sail through? Good grief no!! You should see my grey hairs and there are days I feel like locking myself in the shed and refusing to come out.

I really get the button pushing thing. My 9 year old knows where all my buttons are and which order to press them to get mums head to explode :o. But I've been through this once and while my 16 year old seems to be emerging from the utter hell of teenage years, she still has her moments and my girls are wildly different so 9 year old is finding new ways to drive me crazy.

I feel like I'm still winging it. I've been a mum for nearly 17 years and still feel like I have no clue sometimes. But I know that answering you back and being rude is horrible, but if that's the worst thing she ever does then you've done a good job.

This post did make me wonder about people sailing through etc. I've had a particularly trying afternoon with my ten year old (not her behaviour, just the sheer AMOUNT of emotional energy needed to support her through difficult situations on such a regular basis - I think she is particularly high maintenance ) but I thought of all the hours I spent with friends discussing the trial of babies eg feeding, sleeping. Then you get through all that and don't seem to talk about the next phases so much - I wonder why we don't talk about it in the same way. And of course I do speak to my friends about DD, but in some situations it isn't fair to talk to my friends (who might be the parents of her friends) as it feels like betraying her a bit...- she comes across to most people as the beautiful, kind, confident child she generally is! And I suppose the whole fully shared experience of first time parenting, maternity leave, desperation (to some extent), doesn't exist anymore .....

Sail through. God no! In fact I will admit some of my least finest parenting moments have happened since dd started this stage and have involved both her and I yelling and flouncing because yep they really do know which buttons to push.
It is just that I am 3 years Into those preteen years and know that it doesn't go away overnight. I have also laughed toy myself when I've heard ds thump up the stairs mumbling that she hates me because I remember doing that very same thing. I actually relate to the teenage angst and strops far better than the toddler tantrums because I remember being that girl. I remember the horror of hormones and growing up even though it was a looooong time ago now. And I know that my parents were never overly harsh with it. They told me what was unacceptable in a calm and gentle way and most of the time just let me get on with it while ignoring me. They told me as an adult that you just need to have faith in your own parenting that you have instilled enough of the right behaviours over the years to hope that it doesn't comtinue into adulthood. And the reality is that it stops. The hormones settle down, the more mature person appears. I also remember that I must be doing something right. Dd only behaves like that at home where it is safe to test the boundaries and let off steam she doesn't do it anywhere else.