Tenant coming after me for not renewing lease

[Ryan Camenisch]

In May of this year I told a tenant I would not be renewing her lease due to a variety of issues my PM has had with her, primarily being late on rent every single month and not communicating or responding to his correspondence. 

Anyhow, she went absolutely nuts and started calling and texting me day after day and has now filed a complaint with the Fair Housing Council and has taken to attacking/harassing me online. 

As a realtor, I know I am not discriminating based on any protected class and I do want to lease her unit out to a family friend who needs a place to live. Is this a sufficient reason for not renewing her lease? Do I even need to provide a reason for non-renewal? 

Am I in the wrong and do I need to worry about any legal recourse?

Any real estate attorneys or seasoned landlords who can weigh in, I will be very grateful.