sick of Not having sex

I haven't had sex since early OCTOBER!!!!! My husband just won't have sex with me. He's not cheating I'm with him just about 24hrs a day (he works from home and I'm a housewife). He just can't get hard, he's tried medication and therapy and nothing has helped. It's as if he's content with a sexless relationship. He says," he gets all up in his head and gets nervous" when I initiate sex. 
My feeling are beyond hurt because I feel like I'm being rejected I'm sick of "trying" to have sex for it not to work. I just don't get it we used to have great sex now I feel like I have a roommate who I share the bed with. There's absolutely no passion in our relTionship. Gosh I'm so sad writing this stupid fucking post I can't stop crying. And when I bring up my feelings to him he gets super sad and feels like a failure and I feel like a horrible person for upsetting him