No sexual attraction

I've been with my boyfriend just about a year - he's respectful, caring, understanding, non-abusive, college educated with a well paying financial job, has a very "secure" attachment style, lovely family, etc. For me, it's a dream come true - on paper. For the past 6-9 months, I've become steadily less attracted to him on a sexually intimate level and have actually reached the point where the thought of sex (with anyone, not exclusive to him) is physically repulsive. He doesn't pester me for sex, but makes it known occasionally that he's "dying" because it's been a couple of weeks or so since the last time. Usually at that point, I'll get fairly drunk in order to be able to get through the deed (sober sex is out of the question - I experience no arousal /desire what-so-ever). 
I don't want to have to get wasted to be comfortable physically with him because I do love him on an emotional level. This is honestly the healthiest (emotional) relationship I've ever had. I'm really at a loss as to what to do because I feel like a disappointment and I think it's unfair to him to be in such a sexless relationship. 
For reference, I am 27 and he is 30. We both work full time, do not live together, and typically only see each other on weekends due to our schedules.