Nothing is ever wasted. If you have a bad experience, God will always take that and create a blessing from it, if you will allow it. In every experience, "bad" or "good," we can always learn something about ourselves and our false beliefs and our relationship with Him, and we can always come to see the Christ in the person with whom we had the experience --- if we will allow for this growth by letting God's Light shine through us. Are you willing to drop the anger, resentment, bitterness, betrayal, etc? Remember, it is always about your peace. Every experience, "good" or "bad," can be used to bring us closer to Him.