“Irreconcilable differences” is a legal term and the most common reason for granting a no-fault divorce. Some states use the terms irremediable breakdown, irretrievable breakdown, or incompatibility, but basically they all mean the same thing: The existence of significant differences between a married couple that are so great and beyond resolution as to make the marriage unworkable, and for which the law permits a divorce.
Most states have some form of no-fault divorce now, though some states require extensive waiting periods before granting the final dissolution of marriage. (Your divorce will be governed by laws of the state within which you and your spouse live.) No-fault divorces were created to avoid the messy, painful and expensive process of establishing that one person was to blame or totally responsible for the breakup. Prior to no-fault divorces, divorce was handled as a breach of contract. So even in cases where the separa- tion was amicable and mutual, someone had to be painted as the bad guy in front of a judge. No-fault divorce removes that necessity (though some divorcing parties still opt for various reasons to go the “breach of marital contract” route). Judges routinely grant a divorce as long as the spouse seeking the dissolution states that the couple has irreconcilable differences. By law, if one party says the marriage is irretrievable and refuses to reconcile, then such differences are proven to exist.