It didn't take me long to hit it when my new husband (#2) returned to drinking after a near-death experience with liver disease. I would come home from looking for a SECOND job to support us, only to find him passed out on the sofa.
I believe the coup de grace was when, after I had told him we would have to find another place to live because we could no longer afford the rent on house we were renting, he went and signed another six month lease expressly against my wishes. (He had NO job--I was the sole support at that time.) I told him he signed the lease, he could deal with the rent, and I moved out within a couple of weeks after that. I left him one month's rent. I found an apartment, handled the move myself. I divorced him about a year later.