Speak well of your friends, of your enemies say nothing. God sends us our relatives but we can choose our friends. Being friendly doesn't cost anything. A blazing friendship goes out in a flash. Your best friend is yourself.
Friendship is a two-way street.
Sudden friendship, sure repentance. A common enemy makes friends. Fortune makes friends, misfortune tries them. He who laughs at other's woes finds few friends and many foes.