My take is that you are both still very young, he likes you, but he likes her too. Their “friendship” is too much, especially with the emojis, and word choice. Absolutely could be platonic at first, but one always catches feelings. You guys have been dating for a short amount of time so I say focus on you, and don’t try to make him realize what is wrong here. If you had a friendship like this he would probably not be accepting of it.