From a cursory reading of the relevant statute, you have no grounds for an anullment. Better go the divorce route.
Idaho Statutes
TITLE 32 DOMESTIC RELATIONS
CHAPTER 5 ANNULMENT OF MARRIAGE
32-501. GROUNDS OF ANNULMENT. A marriage may be annulled for any of the
following causes, existing at the time of the marriage:
1. That the party in whose behalf it is sought to have the marriage
annulled was under the age of legal consent, and such marriage was contracted without the consent of his or her parents or guardian, or persons having charge of him or her; unless, after attaining the age of consent, such party for any time freely cohabits with the other as husband or wife;
2. That the former husband or wife of either party was living, and the
marriage with such former husband or wife was then in force;
3. That either party was of unsound mind, unless such party, after coming
to reason, freely cohabited with the other as husband or wife;
4. That the consent of either party was obtained by fraud, unless such
party afterward, with full knowledge of the facts constituting the fraud,
freely cohabited with the other as husband or wife;
5. That the consent of either party was obtained by force, unless such
party afterwards freely cohabited with the other as husband or wife;
6. That either party was, at the time of marriage, physically incapable
of entering into the married state, and such incapacity continues, and appears to be incurable.
The entire code can be found here:
http://www3.state.id.us/cgi-bin/newidst?sctid=320050001.K