You should have the diabetes status checked as the immunocompromised state may prone a person to repeated infection.
The second thing is that you should maintain a good groin hygiene and drink a lot of water.The cranberry juice helps to fight the urine infection in a natural way.
Meanwhile have a urine test, r/e, culture/sensitivity to find the causative organism and start the antibiotics accordingly.
The other causes of increased urinary frequency are :
(not a common cause)
Medicines such as water pills (diuretics)
Radiation therapy to the pelvis, used to treat certain cancers
Stroke and other brain or nervous system diseases
Tumor or growth in the pelvis
You should consult a urologist
and have the test done as mentioned above and also have the sonography
of lower abdomen done to rule out other causes.
The definite treatment is according to underlying cause.