Fear didn't do anything for me to keep me sober. Any sobriety that is conditional on a situation or a feeling is temporary by definition, in my opinion.
What if that fear goes away? What if that marriage ends for other reasons? What if I become unemployed and don't have a job anyway? What if I suffer a spiritual crisis or my mental health is shaken? What if I become convinced that I have been abandoned by my Creator, or that He does not exist? What then? Will I drink?
For me, the only answer was to make the solemn commitment that I will never drink again, no matter what. That ability can only come from one source, and that is from me. I decided to do it, and I did.