Brief Answer:
Several possibilities....

Detailed Answer:
I read your question carefully and I understand your concern.

There can be several causes to loss of balance. One common cause is often problems with the inner ear. The inner ear together with the nervous system are responsible for balance so any issue affecting it may lead to balance issues. Usually it is in the form of vertigo, a spinning sensation and increased when changing head position. If that is what you are experiencing then symptoms might be alleviated by use of a medication called meclizine.

If not other possibilities should be considered. One other possibility would be a brain lesion to the brain areas responsible for balance such as the cerebellum (little brain). If the onset of this balance issue was sudden a stroke would be more likely, while if more progressive other types of lesions such as tumors might need to be excluded.

Another possibility would be damage of the peripheral nerves from diabetes. Peripheral nerves are one of the most commonly affected sites from long standing diabetes. Without their input regarding to the brain (the brain needs to analyze all external information in order to make balance adjustments) balance can also be affected. So while you state that diabetes is not the problem I wouldn't be so quick to dismiss it.

So if ear disorders are excluded a neurological exam is necessary to look for neurological signs indicating involvement of the brain or of peripheral nerves and according to the findings proceeding with appropriate tests such as MRI or nerve conduction studies.

I remain at your disposal for other questions.

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