17YO DD went to her (nice) boyfriend's yesterday afternoon. She phoned home in the early evening. DH, her father answered then put her on to me at DD's request. She asked if it was ok to spend the night there. I said she had no clean clothes, make-up which she never goes out without etc, with her and things to do but she was adamant that didn't matter. (She has stayed over previously.) Recently I've told her she doesn't need to ask if she can do things as she just goes ahead and does them if I advise against it anyway, so she should take responsibility for her choices and just tell her DF and me where she is etc - she's pretty sensible.
An hour later DH remembered that a private pupil of DD had called round expecting a session with DD that DD had obviously forgotten about so I called, pupil's phone number in hand to let DD know to ring her and offered to drive DD and BF home so she'd have clean undies etc today. DD declined the offer and asked me to text her her pupil's number as that would be easier for her than her taking a note of it apparently 
. When I texted with the number I included a quite long message about how it's fine for her to require her BF to be as considerate with her as she is with him and stick to living the way she prefers to (ie say no to staying over if he hasn't asked her before she left home)
Just before this I'd been on DD's FB page - she added me as a friend recently for convenience when she was abroad - and looked at a photo of her BF wearing face paints (for a jokey thing). Stupidly I clicked on his name and got on to his page, on which was a very recent jokey status about him disappointing DD by telling her he was gay. Clearly a 'joke'. Even more stupidly though, when DD then texted again, to tell me she'd rearranged the tutoring session I joked about this status, thinking I was being funny.
When she got home DD said she was furious I'd been looking at BF's FB - the joke status was put up by her as a frape, 'facebook rape'and BF was offended when she showed him my texts "accusing him of not respecting her". I apologised for offending her BF and accepted her assertion that she was genuinely happy to be at BF's home without her make-up etc and attempted to explain what I'd meant in my long message (which ended 'love from mum'). DD claimed I hadn't meant my message kindly, wouldn't accept my apology and was unrepentant about showing my texts to her BF - apparently they each know the other's phone passwords.
She has previous history of stirring - reporting any uncomplimentary remarks about DH and me made by her friends/BF and once a teacher 
back to me and enjoying me stupidly taking the bait and giving her a reaction. When DH and I told her off for letting BF see my ill-judged texts that weren't meant for him she continued to do her drama queen bit. She unfriended me and instructed her friend who yesterday made a friend request to me (!) to withdraw it! Although I'm secretly disappointed, I told DD that the unfriending was a good idea as I hadn't enjoyed seeing her drinking-game video and similar. It actually probably is a good idea - she was 'annoyed' when I failed to like their 'In a relationship' status, annoyed when I liked photos of her ....
Now DD and I are furious with each other - I want to cancel her phone contract and she apparently doesn't give two hoots for the fact I've let her Bf spend nights here (from the very first time he came over when we didn't know they were dating) been kind and welcoming, cooked nice meals, followed her instructions about not asking him any questions.... All because I looked at his FB and dared to make a joke. She also said that if I'd said it wasn't ok to stop over at the BF's she'd have been annoyed, but she'd have come home! That would have been a first and I said I'd drive them both back anyway.
Where to go from here? - I'm fed up of her stirring and expecting me to know exactly what to say/what not to say at all times.
Sorry this is so long and ridiculous but I feel so stupid, frustrated and disappointed.