You feel guilty for cheating or your selfishness? Or both? Your a jackass... Be a man and take care of your wife and your infant daughter. If you have to play; play, and dont let them find out.
If your selfishness gets the better of you and you decide to leave them, she will ask why. At least be man enough to tell her the real reason your leaving. You will....
...Say, "honey, its me not you. I just no longer find your pussy desireable. I must fulfill my sexual urges through dirty whores; therefore, i must leave you and the baby. Oh and im keeping the house, and i dont plan to pay child support. Oh, by the way you should consider hiring a personal trainer, you really let yourself go after the baby. And, can we still be friends."