Matilda, the boat metaphor can only be taken so far. The reason your husband is now acting like this possibly is because you've given off new indications that you're feeling independent and want to cut loose from him.
I think getting away from him for a while is a good idea. For once let him come to you. For once you be hard to get for him. It's not like he's never turned away from you. Being poly is not the same thing as cheating on one's wife. Polyamory is always honest and above board. Polyamory is not happening yet in this marriage no matter what your husband wants to think.
Matilda, you've been through enough. Time to not go through anything anymore.