Wow, I can't believe it's almost a year since I posted in this thread....
We have had DD in counselling for depression which has helped a bit, also on meds which helped a LOT both with her depression & with her attitude (unexpected but a welcome result).
I was very reluctant to have her on medication at her age, but it was after months of counselling, also my mother & I both suffer depression so there is a history there.
She stopped taking them a few weeks ago & is back to her old self with the attitude & arguing.

We had an incident the other night - I won't go over the whole thing again but I posted about it, will add the link - she ripped our screen door completey off the hinges
She is grounded until Monday night, yesterday she tells me this is very unfair 'nobody gets grounded anymore' I said 'well how many people are telling their parents to F- off?' and she said 'quite a lot actually'. I said well good for them but in this house we don't do that without consequences

Then yesterday afternoon we were discussing buying her a hairpiece for Physie (dance / exercise) which I am expecting to be around $100. She wants a looong one & someone said it would be more like $170. We can't afford that. This leads to another 'discussion'. From there we go to the shopping centre, and she wants proper sleepers, because her ears are getting infected from cheap earrings. Fine I say, you can have a pair. She says well I have 3 sets of piercings. Hmmm. I say 'you did them yourself...I never agreed to all those.. I can do one set for you this week.
So she sulks & glares & carries on...we have another huge argument ending with both of us in tears. During this argument I ran down teh list of things we have to get / pay for this week, and how much money we have to do it...trying to explain why a pair of earrings can make a difference...and she says you don't have to tell me all that...I said well I'm trying to make you understand. She says 'well you buy a lot of crap, too' and I said well, we work for it, we decide where it goes and she interrupts & says 'yeah and you have CHILDREN!' which is when I lost it, because yes we do indeed have FOUR children and we spend more on her than on the others put together

I went up to her room after we got home & said look, I love you very much and I am really trying to calm down...I hate it when you swear at me and I really have to work to keep my cool. And she said 'well, it got your attention, didn't it?' I said 'what the... so how do I get YOUR attention then?' and she said 'I don't really give a s*** if you tell me to F- off' which is when I walked away & said well I tried
I went & sat downstairs & just cried ...what on earth do I do, I have no idea when she's like this.
And I KNOW that I am reacting badly, I end up yelling & swearing (not at her, just in general but still not good) - she really pushes my buttons. I feel like she WANTS a fight though, she knows what to say & she does it just to get that reaction.
I said to her counsellor I feel like her emotional punching bag

Sorry for the huge vent....