No. I remove them from my life and forget about them.
As
@epronovost implied, the advice to love one's enemies is not in the interest of the one loving, but of the enemy. It appears in the Bible along with a variety of other claims such as it is blessed to be meek or to offer your enemy the other cheek to smite as part of an attempt to cause people to tolerate exploitation without rising up. It's all about submitting to the more powerful without complaint. Be long-suffering. Your reward will come after death if you just accept your lot without resistance or objection now. That's what kings and emperors want out of religion. Here are some people who agree:
- "How can you have order in a state without religion? For, when one man is dying of hunger near another who is ill of surfeit, he cannot resign himself to this difference unless there is an authority which declares 'God wills it thus.' Religion is excellent stuff for keeping common people quiet. Religion is what keeps the poor from murdering the rich." - Napoleon Bonaparte
- "If you want to control a population and keep them passive ... give them a god to worship" ~ Noam Chomsky
- "Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful." -Seneca the Younger
Love your enemy is advice from an enemy that serves him, not you. Discard enemies from your life as you accumulate friends. That's my advice.
Forgiveness is overrated as well. I don't forgive without a reason, and that reason will always be one that is intended to repair a relationship that still has value. Thus, I forgave my sister for something that I wouldn't forgive a stranger for. That relationship still had value, and we needed to get past our problem to preserve it. With a stranger or in a superficial relationship, there is usually reason to forgive.
That doesn't mean that I actively hold a grudge, just that if I considered somebody's actions unacceptable once, I don't see why that would change. I would add the advice to forgive everybody to the list above of items that enemies would advise others in their own interest.
Hate isn't necessary, but I've never found it to be much of a problem to experience. It's often purifying. And here I am referring not to an emotion like anger or rage, but a cool assessment that somebody or something is loathsome. Some people only improve the world by leaving it.
It is fine to hate them. I consider all of the hatred of the American president to be a healthy reaction to him. It's those that don't hate such behavior and values that I have a problem with.