Husband never wants sex !!

I'm 28 weeks pregnant, with a baby girl, his first, my second. Well we've been having this issue before I even became pregnant. And it's only gotten worse. We have Sex literally once every 2 weeks. I'm so frustrated, and he knows how I feel. He says its just not a priority. Well it is for me!! I'm seriously questioning if this is the type of relationship I want to be in for ever. We've been together for 4 years, and everything else in the relationship is great! Ugh I'm horny and hormonal, such  a bad combination!