In my case BD came relatively early, but I am far from sure that my xh isn't having a second MLC!
He had what I can now see was severe depression in March 2003, and was quite ill in December 2003, the time that my mother (who he was very fond of) became terminally ill.
My mother died early in 2005, and his behaviour changed in July 2005 - I can almost put my finger on the day I became aware of it. BD was October 2005 and he has been in MLC ever since. Total personality change.
I don't think there was a seven and a half year run up to this! More like 2.5 years.
I think my xh is very conflicted at present. He wants his family back (they aren't being very co-operative on this one), and appears to have little idea of how much time has passed, or what he has done in the intervening period.
The relationship with second OW (the first one was a real bunny boiler!) appears strange, I haven't met her, in spite of being invited to dinner (you can't make MLC stuff up) I suspect she has little idea of how much my xh is pursuing me. All I can say is that in her case i wouldn't like it, and i do not encourage it. They met after we were divorced, and as far as I am concerned she is doing nothing wrong. Doesn't mean I want to hang out with her and my xh though.
Although i still feel sadness at time, the pain does go away, and we can look at these strange, strange people with their weird ways of dealing with life.
I suspect that with encouragement I could have him back . . . . but I am not sure his crisis is over, or that I like who he currently is. it will take more than a few invitations to dinner to convince me that all is well in xh-world. I would also want to see fair dealing with OW2. Because we were once married I am not entitled, in my view, to get involved with him while he are with someone else. So I keep the whole thing at arms length.
We don't have the surreal conversations that URworthy has with her xh, nor is my xh anything like as mean, nasty or absent as he was (He surfaced occasionally to spew at us all for about 4 years, not one of the better parts of MLC) but I do feel whenever we talk that we are inhabiting parallel strands of reality.