First of all. Your Pope has already rehabilitated Luther. In case you missed it, Pope Benedict XVI declared that Martin Luther actually wasn’t a heretic. According to the Pope, Luther never intended to split the Catholic Church, which is actually true. He never intended to split, but was trying to invite a dialogue and discussion over the doctrine of justification by faith alone. Many don’t realize this, but the 95 Theses he nailed to the church doors was written in Latin, not German, which was the language of the people. If he was trying to insight a rebellion, he would have written them down in a language the people could understand.
Pope Benedict XVI says that he was trying to cleanse the Catholic Church, and for that should not be condemned.
If you believe the Roman Catholic Church is the pillar of the truth, then you may not like it but you do have to believe it.
To my knowledge no Church ever broke away from the Orthodox, accept for the Roman Catholic Church depending on your interpretation of history. The Orthodox have been involved in a lot of dialogue with Lutherans, Anglicans, and old Catholics. In the 16th century a copy of the Augsburg confession was sent to an Orthodox patriarch. Although he agreed with a good portion of it, he did not accept it as Orthodox. However, the tides have changed in some ways. In 1976 Joseph Ratzinger (later Pope Benedict XVI) suggested that the Augsburg Confession might possibly be recognized as a Catholic statement of faith.