No more desire :(

Denise • My name is Denise Im swedish expecting my second child my son is 7
My boyfriend and I use to be freaky we had sex all the time, as soon as I got pregnant everything changed he has no desire anymore . It's not like I gained weight look different . He did get upset when I got pregnant he did quit his job and other things happen in the family. Now everything is better the besides the sex is lame I always have a desire to have sex. What should I do? Why is it like this?