In order to annul the marriage, you must have a legal ground or basis for the annulment. The grounds are as follows: Consent lacking: (underage, mental infirmity, alcohol, drugs, force, duress, fraud); lack capacity to consummate; marriage prohibited by state law. There also a time frame within which you must bring the action, namely: Underage: Within 1 yr. (by parent if party before age 18) of marriage; Mental infirmity, alcohol, drugs, force, duress, fraud, no capacity to consummate: Within 1 yr. of knowledge; where marriage prohibited by law, 10 yrs.; bigamy, no limit.
If you do not meet any of the preceding grounds, you will need to obtain a divorce. However, you will also need to meet the ground of irreconcilable differences in Wisconsin to obtain a divorce.
Contact the local bar association for a referral to a competent attorney to discuss your legal rights. Good luck.
You can get a divorce any time though you have to live in the state for six months and the county you file in for 30 days. (though by statute the waiting period is 120 days).
You can get the required paperwork at Wisbar.org. I would usually tell you to get attorneys but with that short of a marriage, it is likely just preparing the paperwork and appearing in court.
Wisconsin is a no fault divorce state and the only thing you have to allege is that the marriage is irretriably broken.
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