I am married but in love with my old flame.?

We lost contact for almost 28 years and when I finally found her, i suddenly realized my hidden love for her. We met when I came to her country to work and within 5 days, we became intimate. I felt so much love for her and she too but the problems that we have are, I am married with 2 kids and she is someone mistress and been with him for almost 20 years. Her man found out about it and I was warned and my wife was informed. He forwarded all our lusty emails to my wife and we had a terrible fight. But I still can't forget my lover and hope to see her again, soon. Am I being stupid or should I just leave her for good? She confide to me that she is not happy with her man but just hanging on for the right time to leave him. But she still enjoy having with him and sometimes with me too ( NO MORE). She even dare to tell me of her man ual prowess while I am quite pathetic. What should I do with her? Please help and no criticisms please. This is my first time here and I am desperate for good advise.