You know, as much as she's a manipulative, sneaking, low-down, lying nightmare...it's really not about her.
No contact is an absolutely awesome idea in this case, because you apparently have zero ability to create boundaries with this woman.
No contact is not something you should consider...it's something you need to
do.
At the same time: unless and until you find a new therapist and/or Al-Anon (
I prefer "and" 
) to work thru all the stuff this woman has stirred up in you, you're completely vulnerable to having the same thing happen with a completely different person tomorrow, next week or next year.