Honestly, sometimes I only pray for my enemies because somewhere in the NT we're told that doing so helps bring peace. Or am I wrong? I get my Bible verses confused (I read it straight through, like a novel or something).
Anyway, we are commanded to love our enemies and to pray for them, so I do it. I hate doing it. I mean, I feel ashamed, talking to God (big privilege, after all), and I can't even bring myself to pray for some enemies from relatively long ago without beating down my pride and anger. I think there's also a sense of entitlement at work, at least for me. As in, I feel somehow entitled to forgiveness from God and others, but I somehow feel as if I can hold on to my anger and my un-forgiveness because, well, its ME, right?
What's helped me is thinking about how much I've been forgiven. I'm working on that now, actually. I pray for certain enemies who made my life very difficult for a couple years when I was younger, simply because I...I don't know. I was in a tough spot, being crazy and all, they had more power, and I dared to breathe their air or something. I don't get it. But I pray for them and it doesn't always help immediately, but it pays off in overall growth and maturity and accepting the past, which can be difficult.