I have a lot of advice to give as a young adult, but this advice right here is the best I have:
Surround yourself with people who love you. That sounds obvious, but not all the friends you find will be the right ones. Keep looking until you find them. You’ll know them because they will care about you even if you are standing in your own way. They will tell you things you don’t want to hear. They will fight for you when you stop fighting for yourself, even when they person they have to fight IS you. They will be willing to sacrifice their standing with you to help you be a better person. They will not stand by and watch you struggle. They will use whatever means necessary, including risking your anger and denial, to help you. They will care even when you don’t want them to.
Find these people. Find them and hold on tight to them and never let them go. They will be what saves you when you can no longer face the world alone.