It really concerns me that you are still counting in months as to how many months your Husband has been with the OW 3 years and 7 months (43 months).
You said you wanted advice....you may not like what I have to say, but I think after this long, perhaps it is time for you to change what you are doing, obviously it is not working.
Your Husband is cake-eating, and you allow it.
Time for you to do some 180's just for yourself and your sanity, or things will never change.
There can be no testimony without a test. I am praying to go through this test and come out the other end with a new and better marriage then before.