I'm Doug, and I'm very sorry to hear of your situation. My goal is to provide you with excellent service today. I am a GA licensed attorney.
The cause of action that you are referring to is known as Alienation of Affection. While the state of GA has such a right of action many, many years ago, the legislature eliminated the cause of action on April 4, 1979, thereby preventing any suit for Alienation of Affection from being brought in a Georgia court. So in this respect, you don't have a viable case against the mistress. I am sorry.
On the other hand you certainly have the legal grounds to sue for divorce based on adultery.
If you are interested in divorcing your cheating spouse, I can provide you with information in that regard if you ask.
I understand that you may be disappointed by the Answer you received, as it was not particularly favorable to your situation. Had I been able to provide an Answer which might have given you a successful legal outcome, it would have been my pleasure to do so.
If you have additional questions, you may of course reply back to me and I will be happy to continue to assist you further until your questions have been answered to your satisfaction.
Would you please take a moment to positively rate my service to you based on the understanding of the law I provided by clicking on the rating stars---three stars or more. It is that easy. That is the way I am compensated for having helped you.
Thank you in advance. I wish you the best in your future,