Dear Hopeendures,
I'm very sorry you've been hurt so badly. No one here can know what your husband's particular situation is (mental health or physical health or bad behavior having nothing to do with the first two). And we can't make another adult go to the doctor or receive tests he doesn't want to get. Only you know your entire experience and what those facts and your gut are telling you and what the best approach is for you.
There are a number of mental and physical health issues that can cause or contribute to the behaviors we discuss on this site. Not all cases would fall into the realm of MLC and not all will fall into the realm of Frontotemporal Lobe dementia. I've been assisting a friend with this disorder for several years including accompanying her to specialist appointments. FTD is the most common form of dementia in people under age 60, but since dementia is not generally that common under 60, this is not an overall common disease. And, while some of the symptoms of
FTD can start out similar to a number of other issues, the disease does not progress like MLC. Instead physical issues tend to increase, including muscle weakness and coordination issues, problems chewing and swallowing, with bladder control and bowels, and sufferers may end up in a wheelchair.
I'm a third generation LBS. None of the male MLCers were related so it isn't something hereditary through my family. The symptoms and actions were as described on this site, but none of the men had any other signs of FTD disease, and never developed any. They all eventually admitted the mistakes they made though it was too late to save their marriages.
There are many theories and beliefs about MLC but, from my experience and research, MLC may is a combination of factors, coming to a head in midlife. MLC is thought to be the mother of all depressions and the factors that contribute to that could be hormonal (thus more common in a certain age bracket), genetic, situational, etc. In my H's case, it was likely a perfect storm between a family history of alcoholism, midlife depression, fear of mortality after his father died and his friend was diagnosed with a terminal illness, and his life-long coping mechanisms of compartmentalizing, avoiding, distracting and self-medicating. I have spoken to a number of reputable doctors over the years who absolutely believe MLC exists and at least two who experienced it first hand and ultimately came through it with professional help.
Each person's situation is unique and combines a number of factors. We can't know what the cause of your husband's issues are and you can't force him to do anything. You can only control your own behavior and reactions. I never recommend standing in cases of domestic and/or child abuse and, not every cheater is in midlife crisis. It's also possible your husband is a serial cheater and is not going to change.
It is not easy to stare the facts of our life in the face and see the truth there, but I do believe that most of us have a gut instinct or a "knowing" if we look at our situation with complete honesty and without rose colored glasses. When you are ready, you will know the truth, what is best for you, and what you need to do to protect yourself and your economic security. The most important thing is for you to KNOW YOUR WORTH and accept no less.
I wish you peace and clarity on your journey,
Phoenix