Not sure how normal it is, but I suspect it happens.

I did have a therapist lay down the requirement that I sever ties with my abuser. That was actually one of the best things anyone ever did for me. It wasn't easy. It meant laying down some firm boundaries with my family, but it really was the right thing to do as staying exposed to his abuse kept me in continually poor condition and risk. I didn't keep seeing that therapist for a variety of reason (this wasn't one of them), but he pushed me to make a proactive decision that in the end was best for me.

That does NOT mean I am saying your therapist is right. Just relaying my story. I hadn't thought about it in quite awhile.