Just to toss my 2 cents into this topic:
I am a 27 year old male, 6'6 300lbs, I like long walks on the beach and I am a Cancer. J/K ya'll
Honestly though I have the same problem. I IV heroin daily and take other opiates just about every day and I have noticed that if my libido was like one of those levers that controls the speed of a tractor it would be on turtle instead of rabbit
I haven't had sex in over 7 months and I really couldn't say that I even care. I am not sure what causes it but honestly I am just happy being in love with my heroin instead of some bitch like my ex-fiancee who's just going to cause drama and make me feel like shit. Maybe the heroin is what is causing my libido to be completely shut off, I would assume that it is, but I love it regardless.
OP in my opinion it's the chemicals that are causing your libido to be shut off. I am sure you've already figured that out, but I figured id share. Best of luck man, get in those pants and make em dance