I know the bible says not to hold grudgea and honestly I'm not butis it a sin to not trust anyone or even care about anything anymore? It seems everere so i could make them look good by putting me down. I'm at a point where I'm beginning to get bitter and not wannabe around ppl. is this a sin?
Bitterness is unresolved anger that builds up after time. The dangerous thing about bitterness is that it is like a root that anchors and then grows and it basically taints everything in your life. It is like drinking poison. You only hurt yourself with bitterness.
You can forgive those that have hurt you but it doesn't mean you have to continue a relationship with them. And trust is earned and built slowly as you get to know who a person is. You can't trust everyone because everyone is not trustworthy.
And a lot of people like to do the put downs to build up their own egos, especially on the internet. Just consider the real source of the insults. The Devil will use other people to hurt you whether unbeliever's, fake Christians, members of your own family or whoever is willing to be influenced by him to do his dirty work.
Jesus said don't be surprised if the world hates you because they hated him first. A student is not above his teacher. If they persecuted him then they will persecute you. It's because you do not belong to the world and because the closer you are to God the more the Devil will target you. Let God take care of your enemies because vengeance belongs to God, he will repay.