Android1-
Your post states that you want to have fun....but you don't go on to list what you are doing that is fun...except your one relationship that you discuss.
To me that is a lot of eggs in one basket, and would make it harder for me not to continue feelings for the person you discuss. With all my energy focused on that person it would be hard for me to find out me, and what I think is fun. Rather I would be so caught up in the other that I would continue the same patterns I created in my relationship with my AexH.
I had a long-distance crush after my relationship ended. He is married though, and eventually I had to come to terms with why I found him so attractive during that period in my life. In part it is because I am attracted to drama and energy and charm (all of which my hubby had in full...but the hiden underside of alcoholism was there too).
So I think my challenge to you is what are you doing or would like to do for fun that takes this person out of the equation?