Listen OP, as regards your 'Relate' Counsellor.
I don't know if it's a genuine Relate counsellor, or just some person your partner found, but up until a couple of years ago it was possible to qualify and practice as a Relate counsellor after a year's training of 10 weekends + some essays.
I know this because a friend of the family trained to be a Relate counsellor as an occupation for his retirement.
Before you meet your counsellor, Relate requires you to fill out questionnaires, and if there has been domestic abuse in the relationship they are supposed to refer on to specialists in domestic abuse.
What they are not supposed to do is see the both of you together.
In practice, the aforementioned friend has been referred couples where there is domestic abuse, and he has expressed his concern about to Relate, because he was given no training in abuse (he was simply given a list of books to read on domestic violence), but he has continued to be referred people who are or were in an abusive relationship.
A good, intelligent counsellor would never suggest cutting you off from a good source of support and information (Mumsnet).
You need to stop seeing this counsellor, because your partner is going to use the sessions to abuse you.
I think you need to consider what the reaction of your family would have been if you had showed them this and your previous thread, rather than his family and friend.
I think you know perfectly well that if you talk to anyone in your family about what's going on they will tell you to leave. And they are right. They are obviously good, caring, sensible people.