I don't view anyone in terms of friends and enemies. Those terms trip you up right away. Admittedly it is difficult to avoid remembering negative exeriences you may have had from others and of course it is important to be on guard against attacks. I think it is a matter of looking at the truth or correctness of each statement that comes to your attention who ever speaks it. Ignorance and falsehood are the real enemyt, bad advice can be spoken by anybody, often unintentionally.
Love the friend part of your 'enemy' , hate the enemy part of your 'friend'
It is really about batting back a good return shot whatever is fired at you, like on the tennis court.
The people who wrote the Bible didn't look in great enough detail at the subject of emotional literacy, they didn't seem to be aware of the complexity of their emotional response. They didn't pay enough attention to detail.
I think the riddles of 'love your neighbour & enemy' makes sense if it means aim to be caring and have a correct, unbiased opinion of others, look for the good points in them and acknowledge those while being aware of things about them that you distrust or loathe. Aim for their well being.
Love your neighbour & enemy obviously can't mean trying to make yourself like or love aspects of them that you loathe or to spend time with them when you would rather not. On the other hand Abraham Lincoln said, 'I destroy my enemies by making friends of them'