Take a bite...

Make a list of every word you use on a consistent basis to describe when you're feeling negative emotions. Then make a list of all the words you use to describe, on a consistent basis, words for when you're in a positive mode. Go on, do it now before you read any further. Two things should be apparent. One, we have a great many more negative emotion words than positive ones. And two, our negative words are much more strongly expressive than our positive ones. So now, take the negative words and look for weaker alternatives. Instead of "enraged" you could choose to say "annoyed" for example. Now, take all your positive words and strengthen them up. Instead of "Fine" you could say "I'm fantastic thank you!" Trust me, after a while, you will feel your mood generally improve.