Everyone has said what I want to say, but I wanted to expound on the "not allowed to date", thing.
My husband's first marriage ended when his wife, who had redefined "poly" to mean "I'm going to go sleep around while your responsibility is to stay home and watch your stepson", ended up leaving him for the other partner. She used the same tactics on him —*"you don't trust me", "you're being mean", "you're attacking me" to make his feelings of insecurity into HIS problem, all the while treating him like garbage, trapping and controlling him in this marriage until she got bored with him. It became a self-fulfilling prophecy, with her becoming increasingly abusive, which would leave him even more depressed, which annoyed her and would cause her to step up the abuse…*you get the idea. It was bad news. Your situation is bad news.
This is not healthy. YOU are unhappy and that matters.
Should I stop talking to my boyfriend about this?
NO. You should take control of your own happiness. This is not polyamory. This is abusive. You're better than this and you deserve someone who makes you feel like you matter. DTMFA.
We say all this with love. Guys like your boyfriend are what make it hard for us to tell friends and loved ones we're polyamorous because he uses the word because it seems convenient and stomps all over it. Good luck to you. We're all on your side here.