Married to a bisexual man and feel so confused

Hi, I’ve never posted about this before. But I’m married to a closeted bisexual man. I knew this when we were married although things recently have changed. We have been married for 15 years and have three kids. We really love eachother however recently we’ve been struggling. His attraction to me changes daily and he recently has said that he is no longer attracted to me at all. I guess This means we need separate but he doesn’t want to. He can’t imagine himself in a romantic relationship with a man but he is solely sexually attracted to them, I’m uncomfortable in an open relationship. We haven’t slept together for 6 months and it hurts me. I want a sexual relationship but he is also such a wonderful companion. I don’t know if tomorrow he will want to have sex again or if I have to be celibate. I have to say that if that’s the option I don’t know if I can continue in the marriage but we also both feel very obligated to our kids. Just feeling very alone in this