Hi Madam.
Read your history and understood your problem.
Since you have no sexual exposure, the cause is definitely a local one.
The itching at the
urinary tract, meaning at the urethral opening, which is recurrent can be due to many factors.
This is akin to
balanoposthitis in males.
The local environment at the private parts can be a reason and can cause such a problem.
I would suggest you the following:
First of all get your blood sugar checked as this may be the first sign of
diabetes in elderly patients.
Secondly get other blood and urine tests including culture and sensitivity.
Local care:
Clean the part with plain water and keep it dry with cotton cloth or a hair drier.
You can apply liquid
povidone iodine locally.
Take a 5 day course of an antibiotic and more importantly
metronidazole.
Take a single shot of oral anti-fungal tablet, no more.
And lastly , the most important get a check up done by a Gynecologist to confirm the diagnosis.
Wishing you a permanent cure.