Friends are important. True friends like you for who you are and do not try to change you into someone you do not want to be. They are there for you and you can trust them not to misuse information you share with them in private to hurt or embarrass you.
If a friend starts to treat you badly, being mean to you, or suddenly not being there at all, they may not be a true friend anymore. Knowing when a friend is no longer a true friend can be hard and can hurt a lot. Remember that you deserve real friends who respect you and your feelings.