I feel like people go through life judging people on the things they did, or the things they have said. But I don't think that is a very fair measure to judge a person on. We all say and do things that we really don't mean, or that we regret - it's just an inevitable part of life. So how is it fair to judge an entire person based on that? Thats ONE part of their life.
People look at one event, and never give a person a second chance. But people, we are still young, and we are still learning. People make mistakes, or people get themselves into bad situations. But that doesn't mean they are bad people. You have to be careful when associating yourself with people who are so ready to judge others without knowing (or caring about) the whole story - because think about it, if you screw up - they will probably do the exact same thing to you. Its the way they work. It may suck to face that, but you have to make the choice to keep those people in your life or let them go.
There are some people who are lucky and avoid these slip ups - but no one is perfect (you are naive if you think so). But you never learn life lessons without making some mistakes. Don't let this lull you into a sense of comfort, because at any time - something bad can happen, and you may not know how to pick yourself up from it.
Most importantly. I want to emphasize that not everything you hear will be TRUE. It takes a really big person to listen to both sides of the story (because no matter what you think - there will always be 2 sides.) Don't be so willing to just believe one person's side because it is a good story and everyone is talking about it. Chances are, there are details left out, or details added. Just because it is a good story, doesn't mean it is a completely true story.
And yeah, maybe you want to end a friendship because of something that was done. That is FINE. It is your choice. Just be mature enough to keep it between you and the "ex" friend. Don't make other people choose sides just because you feel hurt.
Love is louder than the temptation to believe or spread gossip. Rise above.