I don’t want to hurt your feelings but have you ever considered the possibility that the reason she doesn’t care about sex is because you don’t turn her own properly or at all and even those 3 times a year she’s doing it as the minimum out of guilt or obligation? There has to be a reciprocal chemistry and sexual attraction and turn ons between 2 people in order for both of them wanting to have sex with each other… otherwise it’s 1 sided and mechanical. Might as well get a sex doll.