He never wants to have sex?

I've been with my SO for almost 2 years now, at first we were like rabbits, now we only do it when it's ovulation time and he never feels like doing it. He claims it's because he gets off too fast, (which he does but that's okay because he always makes sure to 'take care of me first.) He wants me to give him head all the time though. Do you think he's lost a sexual interest in me?