Annulments exist almost in a void in Florida. There is no family law code in Florida that specifically addresses them, and the courts do not assume that any individual has an undeniable right to one. This is not to say that it is impossible to have your marriage annulled in Florida, but you should consult an attorney to make sure you meet requirements that may fall into a gray area.
Divorce is what happens when something has gone wrong in a marriage that cannot be fixed. For an annulment to be granted in Florida, you must convince a judge that the marriage was never valid in the first place.
"Void" versus "Voidable" Marriages
Here Florida makes a distinction. A "void" marriage is one that should never have been permitted by existing law in the first place. A "voidable" marriage is one that had grounds to exist at the start, but something came to light later that should nullify it. For instance, a marriage based on bigamy is a void marriage--it was illegal from the start. If your spouse lied about something fundamental and you married him relying on what he told you, then this would be a "voidable" circumstance. To get an annulment, you're required to prove one or the other.
Since there are no specific statutes in Florida to govern annulment, judges here fall back on existing case law to make a decision. This means they will look at decisions handed down by other judges and try to decide if your case meets the same criteria. For this to happen, a trial is required, and proof of your reasons for annulment must be provided to the court. An annulment will never be granted by default in Florida. A judge will not order such a thing just because your spouse did not respond to your litigation.
According to The Divorce Center, a large group of attorneys who practice family law in several Florida counties, it is very difficult in Florida to prove grounds for annulment. The grounds must involve grievous misrepresentations by one spouse to another. Examples include fraud, duress (he held a gun to your head or otherwise threatened you with dire consequences if you did not marry him), consanguinity (you learned after the wedding that you are related to him by blood), or impotence. Impotence means that one party is incapable of having sex, and it should not be confused with sterility (an inability to procreate). Another potential ground is bigamy. If your spouse was previously married and that marriage never ended by divorce or death, this would be a ground for annulment because it constitutes a "void" marriage.
Since Florida has no judicial code to govern annulments, it is possible to start down this road and go through an entire litigation only to have the judge deny your petition. Even if your marriage meets every single criteria to qualify for an annulment, if the marriage was consummated (if you ever had sex) after you learned of the nullifying circumstance, then Florida will not grant you an annulment.