He either has picked up what his parents have said, did.
Men can be impressionable.

Or his friends are telling him that if he does this to you.
You will do what he says.
Just to keep peace in the family.

Men want to be in control of anyone/everyone!
Ask him to find a doctor mainly a mental health professional.

If he goes on/off!!!
Then ask/tell him to find one if he wants to keep this relationship alive and well!!