Yeast infection won't go away. Been to doctors several times, prescription treatments don't help, have tried natural methods as well. How to fix this?

Re-evaluate. You need to see your doctor for culture of the organism(s). You may have a mixed infection that is only being partially treated. You may even have discomfort from an inflammatory that does not include any infecting organisms.
May need full eval. The first step is to verify that it is indeed a yeast infection. Lab tests will help confirm and also determine what fungus is responsible - some are resistant to the standard meds. Recurrent or persistent yeast infections may indicate either a "resistant" form of yeast or an underlying medical problem such as diabetes. Combinations of meds and "biotherapy" may be necessary.