James, i feel for you.
Sadly, there are many folk who use alcohol in the way you describe, and i believe there is no such thing as "sensible, moderate" drinking for them/us.
If 1976 is your year of birth, then you've probably got 5 more years of overloading your body with poison, (cos that's what alcohol is) before you cause any lasting damage.
Sorry to sound harsh, but i've got the tee shirt. Do yourself a favour James, and sack it. But i suspect you will continue until you reach rock bottom.
I wish you luck x