Fell in love with a married man

So I recently came back from Hawaii and fell in love with a man that I met over there that was also married to another man in the navy. I'm from Sydney and all I wanted to do was have a quick hookup with an American. Who knew that my 1 hour hookup would go for 3 days.I've never felt such a strong connection with someone but it did hurt to know that I was "the other guy". No one had ever looked at me the way he did, and every moment I was with him I never wanted to leave.I honestly have no regrets because those days spent with him were unforgettable. But knowing that he was so unhappy in his marriage just broke my heart. Am I a bad person for continuing to do what I did with him knowing he was married? The look in his eyes when he took me to the airport just killed me. I know he didn't want me to go and I too did not want to leave.