we both drink but he doesn't like when I do...

My boyfriend and I both drink. We both come home and have a beer and both enjoy a night out.
He will drink a whole 18 pack alone. 
But recently told me "you drink to much" and wants me to stop.
I'm confused. I have maybe three beers and done.
How do I drink to much?????  At least compared to him.
Why would he say this? Especially when HEs the real drinker.
Just venting