Reasons

Why ask "why?"

I was stuck going 'round and 'round in my head trying to decipher why my husband was acting the way he was. Why was he treating me the way he did? Was any of it my fault? What was I responsible for and what did I need to do about it?

It could have been that part of the neglect was coming from his depression. Since I suffer from Major Depression, I felt I should support him and be more empathic.

It could have been that the with holding of information was memory issues and not intentional. Either as side effects of his medications, his brain surgery, or possibly due to lack of oxygen to his brain from his partially collapsed lung and the fact he refused to even cut down on his smoking. I felt I should encourage him to get checked out by his doctors.

It could have been that his refusal to enforce any sort of consequences on his children's behavior was tied with his possible Superman Complex, and a need to always be "the good guy". I felt I should support him and push for counseling for himself, his kids, and family counseling sessions as well.

I could go on. The relationship issues were varied and complex.

I did come to realize that my complacency and acceptance of the treatment I received directed what was allowed acceptable behavior. That was my responsibility. 

Asking "why?" was important in sorting out how to approach making changes. Seeking proper treatment for the symptoms requires you figure out the origin, at least in general.

But I got stuck there when I had done all I could do myself and was waiting for him to join me in seeking a healthy relationship. And he didn't.

There comes a time when the "why" stops meaning anything. It doesn't matter anymore if there are no changes being made. No effort. I waited 2 years from the time I demanded he get his kids and himself and us in therapy. I know that change is slow, so my expectations were not linked to a timeline, but things actually deteriorated instead of improving. 

In the end, I had to leave because I came to realize that one way or another, staying would kill me.

"Why?" matters not if I cease to exist.