Moving the money from a joint bank account to one in just your own name won't change how it's divided in the event of a divorce, but it will change who controls it in the meantime.  You aren't breaking any laws by doing it now (once a divorce was started, that would no longer be true, most likely).  You should also make sure that you have control of all the financial information you can find.

A local divorce attorney can review all the unique details of your situation, and give you reliable advice before you act.  It's the best approach.

It is advisable to at least take half of the money and put it into an account in your own name, as otherwise, your fears could be realized. In Florida, it doesn't matter whose name an asset is in (and the money in the bank accounts is an asset), it matters when it was acquired in order to determine whether it is a marital asset subject to equitable distribution. There are also probably multiple other issues regarding debt and assets that are going to arise that would need to be resolved, and it is definitely advisable that you retain an attorney to assist you in understanding your potential rights and options during a divorce proceeding.

My office offers free initial telephone consultation if you would like to discuss your matter further. Should you wish to schedule a telephone consultation, please contact my office at 407-971-6140 so that we can discuss your matter in more detail.