Sibling Experimentation

Since last year, my older sister (47) and I both went through life-altering changes. We've always been close, but our respective divorces, layoffs and other problems brought us together under the same roof. Long story short, we've become closer than what would be considered "normal" for siblings, and we've now become a romantic and sexual couple of sorts. We started to become as public as one can be with such a thing in the last few months of last year.
Our relationship was always unusual. We always touched each other in ways that weren't usual for siblings, and some people (including our parents) were weirded out by our behavior, so we kept it in check. But there was an underlying attraction, we could say. There were some outbursts of it. Once, when I was about 17 and my sister 19, she gave me a playful kiss on the lips. It became nothing more and it never happened again, but it was kind of magical. The kind of magic I haven't really experienced with any of the partners in my life, not even with my exwife.
So, living under the same roof for months, with a little push from some wine every now and then, we ended up giving in to that attraction. We know it's wrong. We also know we've been having the best sex we've ever had. And we figured: we're two responsible adults, with no extended family, we are attracted to each other, there's love, there's a strong attraction, she can't get pregnant (one of the reasons her husband divorced her) and it's hot as hell, Why not make love between siblings under these conditions?
We "date" openly and publicly, but we try to avoid places where some undersirable eyes could catch us. None of our neighbors really know us where we live now, so we pretend to be a couple (one of the advantages of sharing a last name) and we make love freely and openly. Our closest friends, while weirded out by it at first, are cool with our relationship, and they're all we need. They just refrain from asking too many questions, which is understandable.