Let me see if I can help. The Bible also says, "he who hates his brother without cause is a murderer." My understanding of the scriptures is that when the term "brother" is used, it is referring to brothers (or sisters) in Christ. Do you really believe this psycho-b*tch from hell is sister in Christ? I mean would it even be possible for a sister is Christ to do or say some of the evil things she does and says? I have no guilt about hating her, and I believe that if she were a sister in Christ that God would cause my conscience to experience guilt.
Now, that "Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you" can be a bit of problem....so I guess we're back where we started, huh?
I can only say with David, "Is there not a cause?"