Solo is right, it happens but...the dick never lies about pussy, initially.
Straight guys are so eager to achieve sexual conquest, they'll do anything and women know it. Unfortunately, guys never listen to their dick's warning signals before leaping into what becomes a "relationship"...
Here's some possibilities:
Was this the girl friend of your former girlfriend? You know, the one you used to fantasize about when fucking your ex.
Was this the coworker who seemed extra friendly to you but now that you've become intimate, she never stops needling you about your contact info to your cash cow client?
Was this the girl who you accidentally ran into at the laundry mat, bookstore and your brother's wedding? Did she friend you on FaceBook and already know your date of birth, highschool reunion, and your mother's taste in potential daughter in-laws?
Was this the girl that was the most exciting, engaging and spontaneous personality you've gone on a date with in a long time. The one that swept you up in a frenzy of emotion and then disappeared for two weeks. Now, that she's back, she's exciting...engaging...and...spontaneous....?
Ask any middle-age guy if he ever listened to his limp dick prior to slipping his dick into mother nature's ATM machine.
Infidelity
Ambition
Obsession
Schizophrenia
Guys think they are depositing.
Woman know it only debits....or you could have been drunk.
just a thought.