"Dating" likely isn't an issue. What often goes along with dating, I think, is what you're really curious about. The statute you cited is the correct statute for the situation, and under that statute, the 22 year old will avoid prosecution. As far as the guardian consent issue, I don't understand where you're getting that from (perhaps an older version of the law?). Guardian consent isn't an issue to this crime as far as I can tell.
There are some other things to consider. First, regardless of the criminal statutes, you should consider the input of your guardian. She has your best interest in mind.
Second, you should be aware that there are sexual performance laws that prohibit certain conduct of a minor (under 18). Basically, avoid cell phone snapshots and similar media. Here is the link to that statute: http://law.onecle.com/florida/crimes/827.071.html
The above answer is not intended as legal advice. For a more complete analysis of your situation, you should contact an attorney to schedule a consultation where all of the necessary facts can be revealed.