Am I required to provide my private medical records to my ex spouse

I am sorry to hear of your diagnosis, and that your ex is attempting to access your records during this difficult time.   In answer to your question, yes, your medical records are highly confidential.  There are certain circumstances in which a court will permit some or all of your medical records to be reviewed, but these are limited to circumstances in which they are legally relevant to your case.  So, for example, if you claim that you cannot work because of your medical limitations, and as a consequence your ex-husband has to pay more support, a court might find that it is appropriate for you to disclose those medical records that are sufficient to verify the nature of your disability and your limitations on employment.  Without knowing more about the facts of your case, it is difficult to say whether they should be released.  However, if you have been served with a subpoena for your medical records, you must object ASAP, and you can file a motion to quash as well.  If you can afford to consult with an attorney in your area I would suggest you do so, due to the somewhat complicated nature of this question and the urgency of your response.