After being married for 5 years, I left my XH. The sitch was a mess but I believe that I had been unhappy for at least a year. I was 1 month shy of my 21st b-day when we married, he was 23. Young, naive and trying too hard to make everyone else around us happy (our families).
My ex's family was very dysfunctional and his Dad was the king of giving him guilt trips. My ex seemed to always put me last on the list of priorities. After working 70+ hours a week, his and his dad's car shop, and our lack of being able to work out problems all took its toll.
We never learned that there are just times that we just needed to agree to disagree. We would fight literally all night long and not resolve anything. The next fight would also include the unresolved stuff from the last fight.
I never felt supported in the things I pursued. Hobbies like writing or making designs with beads. I was told many, many times that I was "selfish" because I had the gall to think about myself and my own needs.
I can't say there was one large thing that made me leave, just lots and lots of little things that I just couldn't deal with anymore, no matter how many times we tried to fix them.
Hope this helps!
JL
Life is not measured in the breaths we take, but in the moments that take our breath away...