apologies for length...
over the last few weeks (months), DD has become ever more rude and disrespectful. of me, DW, and my PIL (who support us a great deal with after-school lifts etc).
she has no tolerance for anyone or anything that doesn't fit what she wants, and makes it very obvious how she feels.
she's often awful to DS1 (she's the oldest, he's the middle one), and seems to make it her life's obsession to ensure that everyone is aware of every little fault/mistake he makes.
she's 14, and is under pressure at school, as has historically been a very high performer (though most of this pressure she puts on herself)
she is spoilt (obviously not her fault), and very entitled as a result.
we've tried talking to her, but we just get further rudeness, and are told "well then people shouldn't annoy me", and things like that.
last night, we went to the shop to get some stuff for her and DS1's lunch today. in the car she was picking her nose, so i called her out on it (as she frequently does when her brother does it). she got all arsey, and as we were walking into the shop, she loudly told me to shut up.
i don't really care what other people think, but this was my tipping point. i told her i was buying lunch for DS1, and that she could sort her own out (we had plenty of stuff at home, we just went out for treats, as it's a weird schoolday today).
i said i'd had enough of her behaving like a twat, and that i wasn't going to put myself out for her anymore, until she started to show a little more respect, and stopped taking everyone for granted.
later in the evening, i'd decided i wasn't going to drop her at her friends on the way to work/school, so i told her this (we live