Everybody had a day in the past when he/ she was in a bad mood.
There are a lot of way to get out of bad feelings. I found it in listening to music and playing the guitar, but everyone has a different personality. There are people who play the piano or the violin or go to the gym and work their heart out of themselves.
If you play melodies you'll be very calm and relaxed. If you play rock n' roll you'll feel yourself unbeatable.
(same when you listen to them)
And it is also fun to play, you feel success if you can play different songs.
It also helps to pay attention on two things at the same time.
And the most valuable benefits of playing an instrument is that you can be one of the most popular in parties :-P.
Hope you have enjoyed my post!