I have 2-1/2 yr old female who does the same thing most of the time. It does get tiring.
 
Are you crate training? If you are, just put her back in her crate for awhile and take her outside again and just keep doing that till she gets the hint. She'll learn quickly that when she potties right away, she gets to stay out of her crate and play. 
Also, how about a tiny treat when she does go? Sometimes that helps to motivate them. 
Good luck!!!
