I'm 25, she's two months off 32.
She doesn't thankfully, she's down for the weekend.
And if I called her a cunt, my mum would be pissed off at me, and I don't like to piss anyone off. She has a really bad relationship with her siblings and sort of insists on a strange harmony between all of us and gets pissed off if any of us start an argument with the other. Although she does agree she talks to me very badly and does speak up for me when she's going on.
Hey, i have horrible siblings too, we get along somehow now, in part because they moved we aren't next to eachother but you basically have two options here.
1) shut up and ignore her, try meditation, to make peace until she is gone, don't let her little comments harm you, spend as little time as possible with her and before you know it she is back in her house, you should try mindfullness regardless.
2) call her a cunt, asshole or @$#£%3 whatever and your mom will be offended, BUT, she doesn't consider your feelings does she? There may be arguments, corrections, apologizes, but sometimes this is the sanest way around, or else you keep up with their bullshit, explain you can't tolerate her attitude.
As always, when there is an earthquake later comes peace, your mom/sister might get mad with you but inside they know what is right and eventually peace comes again