FOMO

So idk if anyone has covered this topic on here, but just right now I'm going through a really bad case of FOMO (Fear Of Missing Out) and it's all because I worry about not being invited to a party, or gathering from my friends. And I want to try and host one but my mom won't let me :/ And yes.. I know.. social media is worse when your comparing yourself to your best friend with a huge friend group and close boyfriend. Which I lowkey always feel like I'm third wheeling. But like it makes sense, she totally deserves that. I'm not mad. Just kind of feel like I should belong in a group too. So I started sitting with this other girl at lunch to get to know her which has helped :) and I know some of her mutual friends too! So I think I can adjust myself to her friend group instead. It just kind of hurts to hear people talking about their big plans for upcoming holidays and I just have to be like oh, so cool! Because it is.. but like ugh. :/ And I love my best friend, but I've only been her friend for so long and havent had the chance to meet other people. So I think it's time I started doing that. And it's like what about school events too? Like the dance, I want to have someone to go with. I just wish I had a cool big group of friends that kids at my school have. And it kind of sucks being the "floater friend." Any advice or help on how to overcome this?