You may qualify for a summary dissolution (please see the link below), but if you want an annulment, you'll have to file an FL-100 petition and check the "nullity" box (please see the 2nd link below, with all the forms and explanations you need).
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It is relatively easy to file for an anullment. However, getting a court to annul a marriage can be tricky even if it is a very short marriage. Without more details a husband and wife having "differences" is not enough.
Essentially for an anullment a party has to show that the marriage was incestuous or bigamous, that a party was too young to marry, was married to another person at the time of the marriage in question, was of unsound mind, did not have the capacity to understand that they were getting married or that they were induced to get married as a direct result of fraud or duress.
My disclaimer - I am a lawyer but I am not your lawyer. I am only offering general advice that is not specific to your case. For you to get advice you should consult and retain a lawyer.
You can't get an annulment just because you "don't like being married"; the marriage license don't come with a "buyer's remorse" clause.
Unless you can prove one of the specific and limited grounds for annulment, (fraud, incapacity, bigamy) you can't get one. It's easier, and cheaper, for the two of you to simply do a summary dissolution (divorce). You won't be single for six months, though, which will give you enough time to think before making the same mistake again.
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