Reconsider my friendship

Hi there! I'm new to this forum.

These days my mind is filled with second thoughts about my friendships. I'm in a small group of friends, we're classmates and we've known each other for 4 years, but we got closer only a year ago. I've shared lots of things about my life, including my anxiety disorder, with them, and I consider them my "best friends". We have a group chat where we plan to hang out or just check in to see if we're doing well; the thing is,lately, whenever I text them and ask them to hang out, no one texts back, or they reply after days, saying that they're busy.

Honestly, I'm not sure if I can call them my "best" friends, I feel like I'm the only one caring about this group; plus, I always get crazy anxious when I'm about to text them, because deep down I know they won't reply or they're with other people.

I'm starting to believe that it's all a lie: I feel like they've never cared about me, they stayed with me because I was alone in my class, broken and hurt. I'm still healing, and I know I need to move on and make new friends but it's hard; on the other hand, I still care about them. Any suggestions?