Sending my welcome to you,
Justme$ 
First of all I applaud yet another of Swimmy55's thought-provoking comments...
"...their happiness, them wanting to get help is an inside job and doesn't come from us, their parents." How well said...and how true! The main hurdle for us parents is to convince ourselves that is a fact. It is!
Secondly I applaud you for being pro-active in having your own therapist. While I think this forum is a wonderful tool that can be used to help in our healing, having a one-on-one with a professional can be pivotal.
We have been on this tumultuous journey with our ubpd daughter for over 40 years...surpise (but welcomed by us!) pregnancies...her financial, relationship, you-name-it problems. I am 79 and living through a now 5 year period of being estranged from her (for sure not the first time...but now the longest). Until I came to this forum a few years back, I was always seeking the magic button that would turn things around. I pursued the dream of what I wanted "family" to be with her. I couldn't accept that this WAS our life...wouldn't make moves to get on and deal with what was. As I would pour out my heart in my posts, I would get replies from wisened people similar to Swimmy55. I will admit that it took me a while to stop crying in my beer (oh...I don't drink beer

) and start focussing/absorbing what they were telling me.
You ask..."How do I cope?" Well...you start by being kind to yourself. You work on shedding that role of "Victim" as opposed to her roll as "Bully." You stop believing her labelling of you to be true. My main mantra is...
"I did the best I could and when I knew better I did better...and will continue to do so." Never, ever have I faultered when I have repeated that! Betcha the same for you.
For my husband and myself, we know our clocks are ticking faster and faster. As we took a stand in relation to our daughter's continued and escaltinging verbal abuse (which we had been warned could well turn to physical abuse)...her refusals to go into counselling to try to heal our relationship...we are at a standstill and we are prepared it might just not end...in time. I fear...for her...because throughout the troublesome years there have been glimmers of, for want of different words, "the person on the other side." Long ago there were a few apologies with tearful reunions and promises of "never again"...then something (?) would set her off and our hearts would break...again.
While this situation saddens us, it doesn't consume our lives. We really do seek and enjoy the sun that shines as we journey on.
Hope you stick with us, Justme$, because as you continue to work with your therapist you will be able to share with others how you are "learning to cope."
Don't forget...as you change...your daughter's axis gets a jolt.
Hugs

from Huat