husband won't put forth any effort

So, we've been together about 4 years. We were really close friends before we became involved. I often feel very lonely because it honestly feels like he doesn't care. Our sex life used to be AMAZING. But we've went from being intimate multiple times a day to only having sex once a week (maybe). And only when he wants it. I've stoped trying to initiate sex because I'm tired of being swatted away and feeling embarrassingly rejected.. He's affectionate but that's it. My birthday just passed and despite me dropping hints he did absolutely nothing. I'm just feeling really confused. Because we were friends before we started dating I saw him during multiple relationships and he was always so romantic with his exes. But with me, there's no effort at all. Am I wrong to be upset?