Anyone can tell you to cheer up. It makes them feel good. But see who pats you on the back for a good job. Those who are not driven by jealousy or envy will do just that. Your true friends are proud of your accomplishments, not jealous of your successes. See if a friend comes to you when you get good news, not just bad news. There are lots of people who are willing to "cheer us up" when things aren't going well. But it's more difficult to find someone who will congratulate us when things are going well.