They're definitely not your friends if they talk to you like that, and I highly doubt that they are right. You're not worthless.
The first bad friends story that comes to mind for me is when I was 12 and my best friend just asked me, "why don't you kill yoirself and make everyone else happier?" Around the same time another best friend read our texts between her and the first friend I mentioned where they were basically just talking about me and how I was jealous of them, things like that. The first friend moved away and I ended up staying friends with the other for a while.
Friend #2 ended up becoming a huge attention seeker, especially if anyone else mentioned having a problem. She'd immediately butt in saying how bad her life was in comparison and saying she had the 'hardest life' out of everyone in our friend group. After one of our friends started going to counselling for depression/anxiety she started faking panic attacks, she'd pretend to hyperventilate, the teacher would send her out of the class and people would see her outside completely fine and laughing as soon as she was out there. She also started to self-harm with a plastic ruler on the school bus, which most of us thought was another attention grab... I mean, she was doing it on a bus with at least 50 people on it.
Most recently it's one of my exes. He was a compulsive liar and spread plenty of rumours about me, and about our other friends. This ended up completely sabotaging my friendships, which is partly my fault for believing him, but still a shitty thing for him to do. He told me that while I was in a hospital our friends had done nothing but complain about me and say I was faking it.. which all turned out to be false.
He lied about a ton of other things as well and if I found proof he'd lied about something he'd go and slag me off to everyone, complaining that whenever he told me something I'd spread it -apparently to him, when I tried to prove that I was being lied to and used, he was the victim.
Honestly I could write a whole book on the bullshit he's done, but to cut things short -I kept forgiving him like an idiot, we got together, he and my friend kept meeting up together and for some reason confirming their plans in group chats I was in (despite them being the only two going), he broke up with me after we had sex for the first time. Then he asked out one of my friends, got rejected, and tried to get back together with me for a few weeks with a series of creepy, sexual comments.
He ended up kissing my friend (the one he met up with a lot while we were together) while she was in a relationship, she then broke up with her boyfriend and now she and my ex are dating. The last thing I heard about him was that around Christmas, he was talking to his girlfriend's friend's friend who he'd only just met, found out he'd recently been to his friends funeral, and made a joke about it. It was only a week or two after he had died, too.
So, sorry my reply came a slight rant. But if there's any advice I can give it's that you should cut out any friends who treat you badly or make you feel terrible. I know for a fact that if I was still friends with my ex or the other two friends I mentioned I'd be feeling a lot worse and much more depressed than I am now, so cutting them out (even if it was hard at the time) was definitely the right thing to do.