We Want To Be Free

My sister and I are lovers. Obviously, it's a secret. We've been in a relationship for a very long time, but it's more than just lust. We've in love with each other.
I had a crush on her since forever (to this day she's a very desirable woman, despite being 41), and she was always very open minded. One day, when I was 16, I was drunk and kissed her, and she just went with it. I lost my virginity to her. It began just as fooling around, but we always had a very close bond. It became love.
It's frustrating because we can't shout it out in the open. For the sake of appearances, we have to do things we don't like. I date every now and then, keeping women around long enough for me to seem like just any other womanizer. My sister even got married, but fortunately her husband is so focused in his work that he's out of town frequently and long enough for us to be together from time to time.
We're very open minded and fortunately, we've found like-minded people in swinger clubs. We go someplace where people know the kind of relationship we have. That's pretty much the only place where we can "date" openly and be sexually fulfilled.