I saw a therapist who believed MLC existed, and that helped me, because I seriously thought I was going crazy. My xh changed so much, and so quickly I wondered if it was me who had changed. A long way down the line, I see it was him, and everything about his life indicates a serious mental breakdown.
I am truly not sure how much choice there was for him, from his perception at the time. I wholly agree that for me, my life is my choices, each and every day, but the MLCer is distorted, and does not see it.
What they lack is the habitual practice of gratitude. Gratitude for what we have, not desolation at what we do not have. Oh yes, easy to say and hard to do.
They rush off thinking that life dealt them a bum hand and that if they change in all their cards life will be OK again. Failing to realise it isn't the cards but how you play 'em.
Mostly I feel so very sorry for our spouses and ex spouses. But it took a long time to get to that place.