I want to date my boyfriend's friend, but he doesn't want me to

Note: To celebrate hitting 1,000 posts about polyamory, I’m taking a break next week and answering any and all questions on other topics. You can submit your non-polyam-related questions (advice and otherwise) all this week!

I have been with my partner for about four months and me and a friend of his are completely infatuated with each other. My partner doesn't want me to have anything other than platonic relationships with his friends but I have no problem if he wanted to date mine. How do I navigate this? He feels completely inferior to this friend and is very insecure about it. But there is a lot of sexual tension between me and his friend because we both want more but we can't do anything about it.

Your partner has been very clear about his preferences: that he does not want you to date his friends. It does not sound like you’ll be able to convince him out of this position, and I don’t recommend that you try. You know the terms of your relationship, which is not to date his friends. Your choice is whether to stay in a relationship on those terms.

You need to decide whether pursuing something with this friend of his is worth blowing up what you have with your current boyfriend. Everything else is a red herring - it doesn’t matter whether you’d be okay with him dating your friends, and it doesn’t really matter why he has this boundary. You can’t change his perspective, you can only decide how to act on the information that you have, which is that you have feelings for someone but pursuing those feelings would be incompatible with the terms of your current relationship.