Chelle
At 6 months you haven´t yet seen how ugly this will become, please read the many threads of others who have had long term relationships with alcoholics. Lying about drinking is only the tip of the iceberg, soon you will realize that all basic norms for human interactions as you´ve known them have disappeared and you´re left to question your own sanity. Alcoholics pull all those close to them into profound suffering, even and especially when they are only trying to help.
I recently saw Leaving Las Vegas after breaking up with my ABf, a bit worried that it would trigger me, but I found it was a sugar-coated depiction of a relationship with an alcoholic - and that is considering that the A in the film has given up entirely on himself! I felt the year and a half I spend with my A was much, much more stressful than what the girl in the film goes through.
Please read as much as you can on this forum and try to internalize that it is true - his alcoholism WILL destroy you. You can´t bargain your way out of it, the longer you´re in contact with this guy, the more you will lose your sense of self and sink with him. The only thing you can do to help is get as far away from him as possible, perhaps - and this is very slight perhaps - that will eventually help him see that he has a problem.