I knew my marriage was falling apart for years, I begged my wife to go to marriage counseling with me for years. I decided that when our daughter graduated High School and went to college I would file for divorce if things weren't at least on a path for improvement. My now ex-wife decided she wanted to split up when our daughter was still in Junior High. Looking back I wish I would have filed years sooner.

I would start collecting all of your family finances, just make sure you know about all of it. Being prepared doesn't mean you have to do anything, but it will mean if you do decided to leave you will be better prepared, also it will keep you from being blindsided like I was if your husband makes your decision for you.

Also you should consult with a lawyer, many will give you a free initial consultation, it will give you information on what you can expect in your state as far as division of assets, alimony, and child support. Once again doing this doesn't mean you have to leave just means that you can make informed choices. Information is power, stock up!