<human>: Condense the text into a few key points

My fiancé and I have been together for almost four years now. For the first 6 months or so the sex was amazing. As time went on, it died down some but we still were having sex frequently. Over the past year and a half our sex life has come to almost a complete stop. We have sex about once a month and she is almost never into it. She as even told me that she has zero interest in sex and views it as a chore. 

I have tried everything I can think of to help her actually want to have sex. I've tried being more helpful around the house so she doesn't have busywork distracting her. I've tried more foreplay (she gets bored and asks me to just do it and get it over with. Ouch.) I've even offered to let her mess around with other guys if that would stimulate her sex drive (getting desperate). She is on birth control - loestrin 24 I believe, but she was off it for a month and that didn't improve her sex drive at all. 

Nothing has worked and her complete lack of a sex drive has frustrated me beyond belief. It doesn't help that I have a very strong sex drive either. We've gotten to the point where I don't even bother asking for ANY sort of sexy fun because it just irritates her. 

I know this sounds cliche, but everything else in our relationship is perfect. She's my best friend and the connection we have is perfect in every way except for sex. We rarely fight, and when we do, we're both very good about working together to resolve it. 

Any input would be greatly appreciated. I'm just a little more bummed than usual about this. :(
<bot>: fiancé used to have great sex drive, now she has no sex drive and no interest in anything sexual. It sucks.