Eight miles isn't that far and I never took my cell phone jogging.
With her bags packed to go home, she suddenly got the irresistible urge to jog on a path she'd never been to before (had to look up the location on Map Quest). ,
If you are working out regularly, you do get an irresistible urge to continue. Taking a jog after getting the packing done sounds reasonable.
If that's the case, maybe she was suicidal.
Apparently people jog at this park quite regularly.
As I wrote earlier, an urge so strong that you will go out jogging without leaving a change of clothes and a towel for a shower after? She was going to head out to the airport in her dirty, sweaty clothes, remain in them for the entirety of a cross-country plane trip?
No woman I know would ever consider this scenario.