You can love that difficult relationship from afar. You can still pray for their happiness and wish good things for them. You don't have to go where they are. It's not unChristian or unloving or un-anything. It's protecting your heart and their heart.
If you have a difficult relationship and you've made it through to the point of the 'forgive me's' or 'agree to disagree' ....for heaven's sake....literally....don't let others tell you how you are supposed to love that difficult relationship! If being where they are to any degree brings you to a place of negativity - don't go there! Do not be bullied.
Prayer, love, and acceptance is hard towards those who we have had conflict with.... but it's worth it - you are worth it! Do what you can to be happy in the relationship ...... and tell all those other negative voices to step back, self evaluate, and take it to Jesus before judging you.... then love on em' some more!
Just some thoughts on a very difficult subject.....