I'm glad you wrote a letter to the counselor giving them a "heads up" on your daughter's behavior. I hope he/she is helpful. This is such a difficult time for us (the S), but our children end up suffering as well, especially with intense feelings of lack of control. That scramble to control the situation (and pain) can really play a number on them.
One of the best things you, as a parent, can do is to not be reactive in the face of anger and name calling (spew). She is seeking attention, any attention. Ignore or be non-reactive in the face of it. If she cusses you out, remain calm and continue with what you were saying. If you were done, just walk away. Don't reward her with a reaction. But on the flip side, reward the good behavior...even go overboard a bit. Reward the good, ignore the bad. If you get a thank you, thank her for being polite. If she picks up her shoes from the entryway without grumbling, take notice and thank her for being considerate. Ask her if she'd like to go shoe shopping (overboard, but pretty darn rewarding). Positive attention for positive behavior. "Catch her being good".
The other piece to the puzzle; firm boundaries. One day without the privilege of driving the car is merely inconvenient. She can then behave badly and know...its only a day. NO CAR speaks volumes. Good behavior earns it BACK for only a day. The car is a privilege, not a right. That's something for her to think about when she is going to choose her actions.
As for her feelings, that's what talking and touching base are about. Validation and active listening are not only great for marriage relationships, they work for kids, too. Find time to ask about her without seeming to pry. Start with spot sharing of your own feelings. "Ugh, I had a frustrating day. How did yours go? Anything fun or exciting?".
Parenting is hard. Parenting with the extra issues of teen angst and separation/divorce issues is harder. My kids are grown (one married) and out of the house and they have a lot of trouble with our "surprise" of impending D and H's MLC. A lot. They still need their mom and dad so it still hurts.
M-51 H-54 2D-27 and 25 M-26 yrs Bombshell and IHS 7-29-15 He moved out 10-3-15 D filed 1-27-16 D final 10-27-16