He asked me how much I told my friends about what we do in the bedroom and I was honest that I am pretty open with my friends since I feel comfortable talking about the topic and am happy to give and receive advice. He on the other hand said that he is a private person and that he is horrified that without asking him if it was ok that I shared all the sex acts that we do and even some kinks we discussed (although to be clear it wasn't anything that wild or embarrassing, pretty tame stuff really).

Even in this comment you are still downplaying what you did wrong. You told your friends not only details about sex acts you and your bf engaged in, but even mentioned kinks that he told you thinking he was telling such information to a trusted intimate partner. You say that it "wasn't that embarrassing," but to somehow how values privacy about their intimate life, finding out that other people heard the full story can be mortifying. You are a really shitty person for sharing such intimate details without first making sure that your partner was ok with it. Also you say that previous partners, "never expressed a reservation" about discussing such topics, but did you actually ask them? I take it my answer is no, but I would hardly be surprised if many of them would have felt the same way as Jason if they knew what you gossiped about behind their backs with your girlfriends.