Tne old saying....."When you dry out a horse thief, what you have is a sober horse thief" may be applicable.
Not all marriages can or should be saved. (some should have never taken place...lol.)
With my children's father (narcissistic personality), I drug him to marriage counseling. He went for a few sessions and dropped out (said that any problems were m y fault and that he shouldn't have to go). So, I went for another year as individual therapy for me.
Then, I got a divorce (3 young children and a professional job).
The children have long grown and that man, from what I have heard, has not changed even one molecule.
To me, the hassle of a divorce is minor to the misery of living in a loveless m arriage day in and day out. It is like a death by a thousand paper cuts.
This is my experience----marriages in a crisis or going through a "difficult patch" where the love (respect, trust, affection) is still intact, underneath...and both are equally motivated...marriage counseling can be very beneficial.
Otherwise...In my experience...when we have lost that loving feelin'....it is gone...it is over.
Like Humptey Dumpdey....
dandylion