A man with a madonna-whore complex is a man who will sleep with and lust for a sexual and beautiful woman but he will never respect her as "wife" material and he will never marry her. In his eyes, she is tainted, impure, unworthy of the status of wife---yet he may possess passionate and contradictory feelings for her. He may even be in love with her but will never allow himself to be with her in any real sense.
He will look for a "good girl" to marry---usually a woman who is cold sexually but, for example, is good at "wifely" domestic things: cooking, cleaning, homemaking in general, etc. A proper, pure "madonna" type woman who will bear his children.