Can my 17-year-old daughter leave the state without parental consent?

The age of majority (ie. legal adulthood) in FL is 18-years-old (unless the minor has been otherwise emancipated through either marriage or by court order). Until then the parents remain the lawful guardians and can exert control over the minors life accordingly; for example, taking responsibility for the minor’s property and taking all legal actions on behalf of the minor.  The guardian also has the right to set the rules, make decisions on behalf of the minor and control the minor’s earnings. Taking it a step further, a parent has the duty to protect and care for their child.

In light of the above, you can forbid your daughter from leaving the state.  If she does, she can be reported as a runaway and be brought back, forcibly if necessary.  In fact, arguably, if something were to happened to her, as a parent you could be held legally responsible for letting her go unsupervised; it would be a breach of your duty of protection and care.

As a practical matter, while you can deny her permission to leave, how you actually enforce that is another matter.  I don't envy your position.  Possibly a consultation with a family counselor is in order.  Best of luck.