The point of this story is this. You need to know what you are dealing with. If there is an active affair (emotional or physical) you are unlikely to turn things around until the affair has been revealed (there are some more experienced veterans here that will delve into this further).
I wish I had been more aggressive in gathering intel.
You need to go to the matresses about this. The stakes are too high to be wrong HEA.
M22,H45,W45 S21/18D12 Retain faith that you will prevail in the end, regardless of the difficulties and at the same time confront the most brutal facts of your current reality, whatever they might be.