"The greatest force in this Universe is that of love, close on loves; heals is that of gratitude." Reiki & Other Rays of Touch Healing
To dispel those who wish harm upon you, get into a slight meditate state and call these folks in one at a time. Say to them, "Thank you! You have made me strong. I respect you and I respect the path that you have chosen for yourself. Now it is time for you to leave." Calling in a general assemblage of people or groups who take issue with you, or you judge also works. What this simple act does is to release the hooks inside of you that serve as magnets for heavy, dark energies.
Then while in this meditative state, turn it around and call in people you have harmed and ask forgiveness. Tell these individuals, "I am sorry! I release any hooks that I may have left in you."