One of the more memorable concepts I got from Divorce Care, which really gave me alot of hope and inspired more determination on my part, was the concept of the Line of Reconciliation as taught by Jim Talley, professional counselor.
He said marriage is like a road and that even in a good marriage people move from being together at the center of the road to being over at the opposite sides of the road because of some conflict.
In a divorce situation one party chooses to get clear off the road.
His observation after years of counseling struggling marriages, is that almost always the person who so badly wanted out of the marriage, will at some point in time come back to the line of reconciliation, have second thoughts, and want to at least try on the marriage, and often reconcile.
The key for the reconciliation to happen is for the person who wanted to stay married to always stay at the line of reconciliation, always ready to accept their partner back and work things out. The number one way to stay in that reconciliation posture is to avoid dating others, because if you do start, you are likely to be off dating when your partner is really serious about working on things and you will miss the golden opportunity.
Jim said the longest wait he has seen was a 12-year gap until the partners reconciled.
(See Separation Links and Separation Books for more info about Dr. Talley.)
For an awesome story of a long term divorce and then reconciliation, see Inverse Ministries and watch the Braggs' testimony. They reconciled after 11 years and living three thousand miles apart.