Because some people consider thoughts to be the basis of their reality, this has a positive effect on their feelings. That is because feelings can be considered the "raw input" that we base our thoughts on. What you feel tries to invoke a knee-jerk reaction, but it is always best to breath first and react after. Blindly acting upon feelings will basically just amplify the tendency of that caused the feelings in the first place.
On the other hand, if you can dilute a negative feeling by adding more positive thoughts, your actions will be less negative, and as such will lead to more positive outcomes. "Getting over it" sure has its advantages.