There are 2 issues. First, is getting her off of the title to the property. This can be handled by having ger execute a deed in your favor. Please note there will be documentary stamps due on this transfer to you. Second, you will need to have her released from the loan by the note holders. This may be a more difficult task. The note holder has no reason to release her from the obligation and may be reluctant to do so. A payment from her/you toward the outstanding amount may be a nice incentive to get this done.
Yes, you do need a real estate lawyer. The lawyer can draw the deed that you need to transfer the house into you name alone. Your lawyer can also negotiate with the lawyer who holds the mortgage about getting your ex-fiance released from liability under the mortgage. As a practical matter, the easiest way to get your ex-fiance off of the mortgage is refinance the property with a bank in your name alone.
Disclaimer: This answer is provided for informational purposes only, does not constitute legal advice, and does not create an attorney-client relationship. Actual legal advice can only be provided after completing a comprehensive consultation in which all of the relevant facts are discussed and reviewed.
I agree with the above contributor, yes, you do need an attorney. It sounds like the solution is for you to modify the mortgage, releasing your ex-fiance and at the same time removing her from title. You will need to work with the attorney who holds the note, and I recommend you have your own counsel to facilitate things. There are a number a good attorneys in Venice, FL that will be able to assist you.
The answers above are all good, but let me drive home for you the most important aspect that I feel you need to be clear about.
There is nothing within you power, your wires power or the power of the two of you TO RELIEVE HER FROM THE NOTE AND MORTGAGE DEBT, except get the lawyer who sold you the property and took back the Purchase Money Mortgage and note to [a] agree to some terms or inducement to let your wife off the note (to eliminate her personal liability and [b] to get that Mortgage Modification and Release of Wife on the Note in writing, properly done and properly recorded.
As suggested above, you might have to agree to pay him off faster or to pay a higher interest rate or to do something to lessen his security (to give up his right to look to either or both of you for what is due him, and to look ONLY to you).
If you want to try to hold down your legal fees, you could try to negotiate with him to see if you can get him to agree to doing the needed release of wires liability and then you could ask him if he would prepare the documentation needed and then take it to your attorney to review what has been presented to you (this can require less time of your lawyer if he does not have to start from scratch in doing the document preparation and getting it accepted by the Lawyer/Mortgagee/Seller.
You should have a lawyer review (if not prepare the documentation) and perhaps negotiate for you unless you are able to do the negotiating effectively. Keep in mind this mortgage has a short life left and consider if you and the wife can ride it out until it "balloons" (i.e. comes due in a lump sum balance payment; that is how I took your summary to indicate).