There could also be a survivorship bias of relationships. The friends you still have are the ones who are willing and able to put up with your shit. The others

There could also be a survivorship bias of relationships. The friends you still have are the ones who are willing and able to put up with your shit. The others are no longer in your life. So when you're around them, you know you can let out your bad side to some extent. You don't know that with random strangers.