Everything that comes into our lives is neutral. People, circumstances, events, relationships, etc. It is all neutral until we label it good or bad in our minds. Remember we create the world around us and our reactions to it. Therefore it is you who chooses to view something as a negative or positive.
You can find a positive spin, lesson, or solution from any "bad" situation. It may take some soul searching and stepping back for a second to look at it, but it can be done. Per the law of attraction what you give you receive. Therefore if you start labeling everything in your life as "bad" or "negative" then you will only bring more of that to you. Instead, label things as positive experiences or lessons, and appreciate the people who have come and gone in your life. This will in turn present more positive experiences into your life.
Look at your life now and see what things you have labeled negatively and look for another angle to view them. You are the only person who can decide that something is good or bad, so why not choose good?!