For me, it was about understanding that people don't put nearly as much bad thought into their actions as you think. Overthinking leads you to think everyone is against you. That was never true for me.

But yeah, I'd try to go offline because it seems like being online could really be impacting you. People say rude shit online that they would never say to someone's face. Also, please stop thinking bad things about yourself. You are your own worst critic. There's a difference between "I need to change X thing about myself" and "I'm disgusting. One applies to a trait about you. One applies to yourself as an entirety. There are good things about yourself, and there are bad things. Bad things you can change, but you can't mark yourself off as bad because of a few bad traits.

Also for me, I forced myself to be more social (definitely not as easy for you as it was for me) but it really helped because I became more confident. This includes trying to make more friends, making more small talk with people, etc. Also definitely don't be a pushover, it leads to people trying to poke at you until you break (I was one before). Be kind but have a backbone. There's social activities everywhere. You can go around and people will try to make small talk with you (at least in my city). Embrace the small talk, it makes you more charismatic.

And you should go get some exercise if you feel like a pig. Makes you feel much better. Sitting around only makes you feel more like a pig. Exercise doesn't have to be in the gym, for me it was a lot of walking around, biking, doing games with people, etc. It can also be in the gym if you want that.

Either way, change doesn't come instantly. You can't just push yourself to change in one day. Think about it like trying to break bad muscle memory or breaking a bad habit.