Every emotion you feel can be neutralized with “This is …”.
From time to time we can feel pain and sadness. With a few simple words and change it into “This is pain” then you can view this emotion by separating from the context of “self”. You’re no longer linking the “pain” with yourself. Instead, you stay aware of this feeling and watch it from the corner. No need to fight against it, what you need to do is to watch it and it’ll diminish along with time.
How about happiness? Watch it from the corner. Don’t feel disappointed when you lose it. Be present when the happiness is present. Be present when the sadness is present. Be present when the hatred is present.
This is emotion. The emotion is not you. It doesn’t last forever.