Many many people quit that way. I think the biggest factor is commitment....you have REALLY got to want to stop and be willing to do anything to achieve sobriety.
I use AA myself, but my husband is 16 months sober through just deciding that enough was enough and making sobriety his goal.
You need to make some big changes though...in attitude, in routines, and in people and places that might trigger.
There are many examples of people on SR who have just used the support here to help them.