In Idaho, we have grounds for divorce that are considered "fault grounds." These are
Extreme Cruelty (mental or physical)
Willful desertion (desertion by a spouse for one year or more)
Willful neglect (failure to provide necessities for a year or more)
Habitual intemperance (addiction to drugs or alcohol)
Conviction of a felony
THEN WE HAVE A "CATCH ALL" NO FAULT GROUND CALLED "Irreconcilable Differences."95 out 100 divorces in Idaho are filed on this ground.
You don't have to have fault. One party to the marriage simply has to say : "I believe that the marriage is broken and there is no hope of reconciliation."
The difference between fault and no-fault is the proof the petitioner must present in order to obtain a decree. Because their is virtually no advantage in terms of property division, custody, or support, the less costly (and by far more often recommended by counsel) approach is the no-fault.
Best wishes for a favorable result, and please rememeber to designate a best answer.
This answer is offered as a public service for general information only and may not be relied upon as legal advice.