I've been married now for almost 4 years and I filed for earlier this month. There really I don't think was ONE particular instance that really sent me over the edge. It was simply the culmination of things that were rapidly going further downhill than I thought possible.
I realized at one point however, that no matter what--- as long as you live with an active alcoholic, stupid $hit is going to happen. It does not matter if it's a major thing such as an arrest or a "minor" thing such as taking out the shower curtain rod and falling into the tub. As long as the person is active, there will always be SOMETHING. I decided that I was no longer willing to bear witness to or be involved in the next "something" that rolled around. I'm done with the stupid $hit.