I am far from being able to be free of negative emotions, but that doesn't mean that I don't understand them, need to transform them, know how to transform them and try to do so every day.
The most important thing to remember is that no one or nothing makes us negative; we are responsible for our own negative emotions and their transformation, and the most difficult negative emotions to get rid of are the ones we are the most justified in having.
The main source of negative emotions is usually our imaginary picture, and expectations of what should happen and then doesn’t. It is also often the result of a situation that reveals our hypocrisy and contradictions.
Suffering is a source of negative emotions. There is necessary suffering and unnecessary suffering. If a brick falls on your foot and it hurts, that is necessary suffering. If you complain and whine about it over and over again, that is unnecessary suffering. Basically, negative emotions are the result of a lack of understanding about something. As long as you feel negative, you will have little ability to think objectively. The irony is, the way out of feeling negative is to think more objectively. Here is a good example: I was once in line at a restaurant, waiting to order something, when I felt someone kick me from behind. I was immediately angry and wanted to turn around to do, I don't know what. When I did turn around, I looked down to see a three-year-old wearing the same kind of camouflage pants I was wearing. He smiled at me, and I could immediately see it was his way to let me know that he was a big boy, wearing the same pants, and he wanted to get my attention and let me know that. My anger immediately turned into humor and good feelings. This is a great example of how negative emotions are an illusion and a lack of understanding of some bigger idea of which we are not aware. It is a great example of having something in me that could, at that moment, observe and see things more objectively.
One thing for sure that is not only worthless but is actually dangerous to your health, is to ignore them entirely and put on a false happy face and pretend you are just fine. That is not transformation but suppression. Sometimes letting off some immediate steam, like saying “ouch” when you get hurt, can be useful, as long as it does not turn into a temper tantrum.
Personally I use humor and creating beauty to transform negativity. Humor for an immediate response, creating beauty to complete the transformation later.