opposing sex drives

my fiance and i have been together for 2.5 years, engaged for almost a year. i am starting to truly fear the future of our sex life... for reference, the first time we ever slept together (5 months of dating, both 22 years old) he couldn't get hard. he got emotional and said it happens and hes super nervous, etc. i helped him through it and over an hour or two later, we achieved. i was scared off at the beginning, trying to distance myself because it kept happening. fast forward, it got a little easier, i fell for his care and effort more than anything (as it should be imo). for the last year and a half, we have sex about once every 3-4 weeks. i go crazy... i masturbate in secret and read smutting books for excitement. im fucking tired yall. we discuss it on REPEAT! every few months i explain that its super important to me that we are intimate more. it doesn't have to be every day, i tried for every other. i even said once a week i can compromise with. about a year in, he started anxiety meds specifically for arousal and they helped. he stopped taking them about 3 months later without telling me. even after we shed tears about this every other month... hes not doing anything about it??? am i supposed to accept this? its making me crave excitement and passion and its also making me insecure that i have a man that rejects me and doesn't want me but once a month... the few friends ive shared this with have said this is totally not normal for a guy, but ive given him time, space, understanding, & genuine forgiveness to figure this out but im coming to terms that this is how he is. my question- does he not care enough to take care of me? are we both dodging the fact that we are sexually incompatible? do others deal with this in their relationship (low drive for man, high for woman)??