Do I have a right to be uncomfortable with this?

My boyfriend and I have been together for 1 year and two months. He’s always there for me, he makes me smile and feel secure around him, he’s funny, and caring, everything I could ask for. Today was a great day besides him bringing up a memory from his past involving some part of his ex… long story short, he used to have this friend that he knew for a year or two and it’s so weird and unsettling for me because his ex friend or old friend, hooked up with his ex too and all of them were broken up including him and her but he mentioned how I shouldn’t feel insecure and this and that and I just mentioned I AM not okay if he’s friends with this guy anymore because it’s inviting the past in one way or another. It’s not even just feeling insecure, it’s not appropriate nor right. I have ZERO friends who were involved with any of my ex boyfriends or guys I dated. Why would he switch up like this? Why can’t he let it go and just respect how I feel?

Do I have a right to be uncomfortable with this?
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