Kirley 15yrs! You poor thing!! Hope everything you're trying now works for you. If you can stick to the yeast and sugar free diet for at least 10 days with all the other therapies you're doing it really should help clear your system and after the 10 days if you don't go nuts with the sugar and yeast I would have thought your flora would be strong enough to ward of any more yeast. But maybe since yours is so chronic you need the yeast and sugar free for longer or as a constant maybe.
Anyway good luck Keep me posted to see how you go