Time to make new friends! Maybe start with the person who wrote the post just before yours.

Facebook has made the word "friend" almost completely devoid of meaning. It's like "literally" or "awesome." Maybe you can DM the loser from the previous post and you two can call each other "friend" until the cows come home.

Better a lack of friends than "friends" that are actively awful towards you. Loneliness definitely sucks, but nothing's so bad as feeling alone when you're surrounded by people who are supposed to be your friends, y'know? As others have said, your slate is now clear to make new, actual friends. And yeah, that can be kinda difficult as a busy person with work or school or whatever else life is throwing at you, but surely there's some sort of starting point - a hobby or recurring thing you attend (in-person or digitally - Online friends may not be able to do all the things that local friends can do, but nevertheless are good to have too).

Then you're not a good fit with that group, for whatever reason. Block them and move on.

Making friends as an adult is especially difficult but it can be quite rewarding. Try finding things you like to do out of the house and meet people there. Also remember to do things for other people and put yourself out there. It can be scary and doesn't always work but it does eventually and you will be better for it. Remember everyone is a little scared even if they don't look it.

They weren't your friends. You were just clinging on the group. You need to make new friends.