Don’t pay attention to what other people say about someone unless it is good. Give each person a fresh start. Deal with them within your own scope, then decide whether they are good or bad. Don’t listen to others, true or not. Slander is very hurtful, destructive, and often not true.
Don’t be judgemental according to what others have decided. Be your own judge. Draw your own conclusions. If the person hurts you…O.K., that’s it! Shake the dust off your feet and move on…never again to shmooze with that person. Depending on the length of the relationship, you may wish to consider reconciliation. In any doubt, do forgive them; be nice to yourself.
We are all fallible. There are no two persons alike.* Even with the closest similarities there are differences. Sometimes these differences cause disturbances that cannot be circumvented. FINE! Tend to your own house, but leave the windows and doors open. Not only will you be looking from the inside out, but those outside will be looking in and get to know you.
(EG: Consider cloning. The clone may look exactly the same as the original and have similar tendencies, but the environment, breeding, and education will be different than the originals and create a diverse personna.)