We don't actually have annulment in WA, the equivalent is asking the court for a declaration of invalidity, and it's only available in extremely limited circumstances because it requires the court finding that the marriage never should have been contracted, for example because one of the parties was too young or already married to someone else. See the acceptable grounds in the statute: http://apps.leg.wa.gov/rcw/default.aspx?cite=26.09.040 Perhaps you could claim there was "fraud involving the essentials of marriage," but then you'd have to prove that emotional stability is an essential of marriage, which sort of goes against the "in sickness and in health" part of the vows. Is there a particular reason you don't want a divorce? You have to jump through all of the same legal hoops, so there is no procedural advantage to invalidity over dissolution...it's actually harder because you have to prove that a valid marriage never actually existed, instead of saying it is now irretrievably broken, which is simply a matter of one of the parties asserting that fact. If there's more to the story, you should absolutely talk to a lawyer.
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