He doesn’t want sex anymore

Me and my boyfriend used to have sex very often, sometimes twice a day. These past couple months things have changed. We have sex once a week or even two weeks now and not because I don’t want to. When I ask him about it or try to have sex he just plays me off or says he’s tired. I’ve expressed how this makes me feel and still nothing. Has anyone dealt with this or does anyone have advice? I feel like this is a bigger deal for me than I’m letting myself feel.

UPDATE

WE FINALLY HAD SEX AFTER TWO LONG WEEKS AND HE CAME ON TO ME THIS TIME