Betrayal hurts in all situations, sometimes it can never be mended, especially if one or both parties do not show forgiveness and becomes hard-hearted over the situation.
Here are some ways I have thought of (in the past 30 minutes) that would help stop this potentially hurting situation from occurring:
1. Keep reminding yourself of the bigger picture. If someone is genuine, they are in a friendship/work/ministry situation where everyone believes in the common vision. Betrayal can occur when someone loses sight of this big vision, either through forgetfulness or being bogged down on smaller issues.
2. Be genuine and work with each other. Don't gossip to others about it, but deal with the issue directly with the person who is involved. Again, if both parties do have that common vision, then both parties should be willing to work with each other in order to stop betrayal from occurring.
3. Actively seek and show forgiveness. Betrayal can be something that one does not purposely intend to do, but for one reason or another, has escalated to that situation. Both parties have to be mature enough to 1. seek forgiveness in the 'betraying' party and 2. show forgiveness for the 'betrayed' party. If both do not occur, there will never be closure in the situation, and this can cause continued friction and distance.
Relationships with friends, workmates and co-workers in the Kingdom of God are fragile and not perfect by any means. Satan will always hone in and agitate these things to see how much damage he can cause. Lets fight against this on all fronts, by focusing on our common vision, being genuine and working with each other, and seeking/showing forgiveness to our brothers and sisters in Christ.