It is a self-evident truth that, in the realm of human relationships, agency will always create the opportunity for truly irreconcilable differences.
During our long-term marriages, we believed we would always be able to think of an acceptable alternative to divorce, no matter what problem arose. However, in both of our cases, the decision was our spouse's. At other times, the kind of marriage a spouse might have to settle for would violate their integrity. For example, we know a man whose wife told him she would stay married to him if she could keep her lesbian partner in a separate bedroom in their house. He would not remain married on those terms.
In situations where your spouse gave up on the marriage, placed serious addictions above the marriage, or proved chronically unfaithful or abusive, you can continue to hope and pray if you wish. This may be living in denial. Acceptance of reality and of your partner's agency is the beginning of healing.
If you are broken-hearted over the decisions of a former spouse and think, "It wasn't supposed to be this way" or that something is "wrong," give yourself time to grieve. But also begin to ask yourself whether, perhaps, your situation is exactly as it should be. Consider whether a chance to start over at mid-life with all the knowledge you have gained is a tender mercy. Begin to think and dream about creating a new future with a spouse that is aligned with you in the most important areas of life – and see your situation for its possibilities.