We just watched the show for the first time. The woman decided that she would rather deal with her allergies so Wrigley could live out the rest of her life at home, than having to spend the rest of her life regretting that decision.

It is good that they know they would keep Wrigley out of the carpeted areas, as that's where dander can accumulate and cause issues, and everyone seemed happy to have Wrigley back home.