Would you describe the attitudes of people you hang out with as negative, grumpy or miserable? If so, Dr. Robin says your own disposition may be in jeopardy. "They're going to invite you to become miserable with them, and that means that they will either seduce you or lure you into their misery by chipping away at your joy [and] by poking fun at your positivity," she says. "They're going to try to short-circuit the fact that you are happy with your life."

While it may be difficult to separate yourself from the people in your life with bad attitudes, Dr. Robin says you should try to cut down the amount of time you spend with them. "Make a decision—if you find that the company you are keeping is way too full of misery, way too full of doubt and judgment and gossip, then just change who you are hanging with and watch your life become transformed," she says.