When is it time?

For me, it was the realization that remaining with the man I considered my soul mate was going to continue to cause me more pain if we stayed together than if I ended it and we were never together again. It had been an ugly year with him having traveled for work for weeks at a time (prior to that he was never gone more than 2 weeks at a time, and that was rare), our first child was a year old so we were still new parents, and he'd started graduate school to get his MBA and was going out partying with his classmates every week. I hated him being gone, and being irresponsible, and he hated coming home because I made his home life miserable fighting with him about his choices - we were totally disconnected from each other's needs.

We managed to pull through it after I told him I was done, and only because we both realized that neither of us would find anyone else who loved us more and would therefore work harder to make a relationship work. We stopped the feedback loop of hurting each other, but it was not pretty. We wouldn't have gotten through it without therapy, and it's one reason whenever my friends struggle with something as big as this, I recommend an objective, professional, 3rd party person to help.

However it turns out TM, I wish you both the best. Life's too short to stay miserable, and marriages aren't easy work, but they are worth the effort if both of you try and truly love each other. The question you have to ask is: is it worth it to fight for?