Quick insights about emotion
Emotion is a constant, except perhaps in states of complete void, but are running in the background for most people without them knowing it. And this is useful because the lens of mental focus of a human should be narrow so they can survive better. When you've found a huge apricot tree on the other side of a great canyon, you'd want to focus entirely on getting across the canyon.
This gets airy-fairy, difficult to understand, but try anyway- you might as well. Instead of learning to depend on things outside of us to create a reaction inside of us. For example, if your emotional state is negative, you may have a thought that says 'listen to music'. Instead of going along with thoughts like these, I'm gonna see what happens if I actually don't, and use my own emotional-state-changing-ability to change it myself, from negative to positive.
Prediction
I predict that what will happen is that my ability to keep my emotional state positive will gradually strengthen as my tendency to depend on outside things to do that weakens.