Have you seen the MTV video clip from the 90s? She says that it is impossible to masturbate without having lust in your heart and that the bible says that lusting in your heart is a sin (as Jimmy Carter so famously recalled). Further, the pitch was that men and women were meant to please each other sexually in a marital relationship, and for a guy to otherwise know how to please himself would spoil that specialness. She was advocating for ‘purity’ at that level, as far as I could tell.As you said, this is a non issue and has nothing to do with her service as a US Senator. Regardless of what you believe about her personal beliefs about moral purity, it should give comfort regardless that she takes her faith that seriously. At least she is not attending a church where the preacher is famous for saying "God Damn America"
She's obviously unfit to be a Senator from a heavily Catholic state like Delaware!