What can I do about a supervisor calling me dumb and I b reported her to HR and was told they didn't feel like it was intentional?

There is not enough information to determine that there may be a legal issue here. There clearly is a human dignity issue, in your supervisor's disrespectful name-calling. But unfortunately, the law does not require a supervisor to respect the innate human dignity of the people s/he supervises. It is unfortunate that your HR department doesn't recognize the damage the supervisor is doing. The best way to combat this is to find a better job with another employer and quit. Be successful and contribute to the success of a competing company.   Michael A. Caldwell