what can i do to prevent breaking off two relationships

So I met this guy recently and I’ve developed feelings for him. I was super excited and decided to tell my friend who’s like a sibling to me. I asked if they wanted to meet him and they were like yes, and I was super happy for them to meet each other. I figured that if my crush met my friend, it would be a comfortable environment for all of us to be in and make a mini friend group. And not to mention, the guy and I have been a bit flirty every now and then or making flirty jokes. But the day I introduced them both it felt like they immediately connected and I felt like a second voice in the group, like if I was barely being talked to. And they were talking mostly amongst themselves since they share a common interest that I don’t really have. So I felt a bit left out and made an excuse to leave the call we were in. And then my friend said the guy had been complimenting them and even found their ***. I didn’t want to be that like jealous narcissistic person, so I brushed it off and thought it was him being nice as a friend. But I cried that night and I’ve still been crying. I can admit my friend is pretty than me, they have already had relationship experiences. I’m so scared my crush will leave me for my friend, and our flirting was just him being whatever. Even my friend admitted to a fear of developing a crush if they hung out with him too much, and asked if I wanted them (my friend) to stop talking with my crush. As much as I wanted to say yes, I told them that if they ever did to tell me and we could figure it out somehow, and they can do whatever they want and that I trust them. But I’ve been so scared and sensitive, my friend even told me they both played together without me. Am I just being too over attached? Am I just being paranoid about the guy finding them prettier both looks and personality wise? I just don’t want to possibly break two relationships if I accidentally say or do something.