Talk about cutting to the chase, and getting down to the important stuff. Wow. The simplest and most effective remedy is also the MOST difficult to actually do. Talk about them, and I don't mean gossip with everyone under the sun. Putting light on the resentment with the person involved is so healthy, and so healing. You don't have to do it on the spot, when tempers may be flairing. But as the old saying goes, if possible, don't let the sun set on the resentment. Without doing this, small resentments collect, and grow into bitterness.
Emdrgreg