Leaving was a process for me. My take on it was this (and many others here have heard me say this over and over): When the pain of staying was greater than the pain of leaving, only then was I ready to take that leap of faith. Because it truly has been faith that has kept me going.
As Anvil said, the pity party is the alcoholic's battle cry. I still have to deal with it since we share a child, but thank goodness I don't have to live with it anymore. Turn it over to your HP and just breathe!