Purging several destructive feelings does not make you insensitive, or reduce your emotional appreciation of happy events. Just because I no longer feel anger or resentment does not mean that tears never fall from my eyes, or that my heart never feels crushed, when suffering is made known to me. Just because I no longer envy others or seek power over their decisions does not mean that I don't feel the joy of beauty, goodness in others, and hope.
Even when anger is not directed toward a person, as when regrettable events occur, this anger is not needed. It is not needed to dismiss blame or purge a sense of injustice. Anger can be completely eliminated from your personality without any ill effects. You can face misfortune with tranquility, and face the misdeeds of others without blaming them. You know how people got to be the way they are. Love of humanity and living in your higher self brings you everything that you could want from your existence.
You care about the happiness and wellbeing of every person. Events may be evil, but people are not. Evil doers are always victims first. We pray for their enlightenment.
Purging destructive feelings does not mean suppressing them. While there are other approaches, the intentional invention of daydreams featuring yourself as a changed person is a proven method. This may result in sleeping dreams having content similar to the daydreams. The method is as follows:
A few time a day, imagine your self with people in circumstances that usually prompt some feeling or action that you want to eliminate from your behavior and feelings. See yourself acting differently and not reacting as usual. See yourself behaving as you wish you would. See yourself not feeling what you usually feel in those circumstances, but feeling empathy or love or understanding or courage as you would wish to feel in those circumstances.
Take every opportunity to act in your waking life more consistent with what you see yourself do in your daydreams.
If this sort of daydream is done a few times a day, you will see changes (verified by others) within a few months. That is my experience and the experience of a great many others.
There is no need for a theory as to why this works. It is an empirical fact.
Write to email@example.com (James Adrian) or firstname.lastname@example.org (Maureen Kelley).