Hence try feeding your brain only nice things nice people to think about. Which intern is your thinking and converts into your feeling. That is the reason I believe our elders always used to say to stay away from bad people. Whenever you feel low, sad and depressed move your thoughts do it however you want change place, article you are reading, people you are talking to, change company, if you really want to have fun with the same people, place give them some time and you to take a break and think why you really enjoyed there or the had times you fought and overcame together. And at the end same pains are unavoidable hence enjoy them too it's one life enjoy, experience what you want and what is destined.