Consult with a local med mal atty to see if you have standing to bring an action. There is a good chance that you dont, but each state has its own rules on these types of cases. There is no private cause of action under HIPAA. I also doubt you have a violation under HIPAA. Inthink it very common for therapists to talk to their patients about other people in their lives, spouses, parents, etc, and ask about their issues. If that was a HIPAA violation, most therapy could not be provided.
You should definitely contact a medical malpractice attorney.
The information provided should not be considered legal advice. I am not licensed to practice in any State other than Ohio. The results of your case will depend on the presentation of evidence, the law and other factors that may change depending on an in depth analysis of the facts of the case. Please see an attorney before making legal decisions.