Well if both previous spouses(yours and your present wife’s) went on to have sexual immorality and you both didn’t prior to meeting each other I would say both of you are in the clear. They broke the marriages because of their own immorality and not yours if I quite understand the situation.
After this amount of time, if you and your present wife are in church, serving the Lord and proclaiming Jesus as Lord...you’ve both been forgiven from what ever sin you might have been guilty of in this regard. Your previous spouses broke your marriages, they put themselves out on the cause of their own immorality.
Just go on loving and being faithful to each other....if you both are fruitful and loving Jesus, that alone tells you how his grace is abounding in your situation!
I would say that SIN is SIN.
I doubt that any is more convoluted in practice than any other.