Is my wife my sister?

I have been married for 25 years to a lovely lady. I know that at birth i was put up for adoption. My parents split up and my mother could not cope with two children. Due to the laws where you can now find out where you came from i have found out that my natural parents lived in Stoke- my wife came from there too. Her maiden name is the same as my mothers married name, my wife said she has a cousin called Susan that lives in London, i have found out that my mothers sister had a daughter called Susan. Friends have said how alike we look. I have to admit that we do have similar facial features. We have three children and two grandchildren. I don`t know if i should share my feelings with my wife about this as we love each other so much and our world would be devastated if we are brother and sister, what next?