Just about everyone stumbles Orieme, most of us multiple times before finally figuring out how to remain sober. Feeling defeated is normal, but thinking that you can "never" change is just your alcoholism trying to tell you that to keep you drinking. Anyone can change, and anyone can quit drinking if they truly want to - including you.
As others have mentioned, instead of just trying the same thing again, you may want to consider tyring something differernt. LIke AA/NA - or maybe counseling, maybe even intensive outpatient treatment. But the bottom line is that whatever you were doing didn't work - dust yourself off and find a new way to make it work.