Feeling like a lousy lay..

My husband and I have been married for 6, almost 7 years. I am 39 weeks pregnant now and he doesn't want to have sex. It's not just when I'm pregnant. He has never wanted to go down on me, won't let me on top because he loses his erection and acts like any position that would benefit me is a chore. He likes what's gonna take care of him and that's about it. I end up unsatisfied and wanting more every time. What can I do to "up my game"? I love my husband so much and really do wish I could do something more to put the spark back... Any advice?