He wrote poetry and letters to “friends.” You have no idea how “faithful” he was or was not. Personally, I don’t care what he did on Saturday nights between the carving the pieta and painting the sistine chapel. Nor should the Church to which he gave them. And you know, in Renaissance Florence, I don’t think the Church did care, at least not very much. It was a little more broad-minded.
He lived to be 90+. I would expect that he found time to repent.