It's a subtle shift, but using the term "woman" reflects a healthy attitude to females that I believe will improve your success with them.
A girl is not yet mature. As a man of high standards and a solid lifestyle, you don't have time for games and immaturity. If you're calling women "girls", you're failing to recognise that they are independent, sexually aware adults.
Lady is a term used to put women on a pedestal. A lady is delicate and has to be treated with kid gloves. Ladies probably do not sully themselves with dirty things like sex. If you're calling women "ladies", you're probably thinking "A beautiful thing like that would never want someone like me." And you're wrong. She wants you. You think you're respecting her by calling her a lady, but you're not. You're failing to respect the fact that she's a sexual creature, and that she's a human, not a godess. She feels uncomfortable on your pedestal, because she knows she's just another person.
The truth is, women love sex. She wants to be with a man who recognises that she is a strong individual with strong desires. She wants to get dirty with you. She wants you to respect that and lead her into fulfilling those desires. She's not always a lady. Sometimes she swears. Sometimes she looks bad. She's not a girl anymore. She doesn't want you to baby her.
So call her a woman.