What pushed me into quitting was health reasons. When they started clearing up after a few months it became easier to forget that reason, but being sober has helped me see all the BS around drinking. I don't think I really realised how much I depended on it until I quit.
The thing that scares me most in terms of relapse is that I will have one of those 'f**k it, what's the point' moments. Even though I know drinking is pointless and doesn't help anything I still have moments where I value my life so little that I'd rather drink it away. But I would have had to seriously have lapsed on my recovery for that to happen.