I'm pretty sure every ride has an 'alternate exit'. But the attractions your wife definitely can't experience (e.g. the ones with the medical warnings) absolutely, 100%, have a way for her to get to exactly where
you will exit the ride - so you don't miss each other.
Some examples:
Test Track - she will likely be escorted by a Cast Member into the elevator they use to move wheelchairs/
ecvs to the exit, then across a short bridge and down another elevator.
Tower of Terror - when you get to the loading area, she will be escorted down a short hallway to the 'back' elevator, and brought down to where the service elevators empty.
Expedition Everest - go through the entire queue (be sure to use the 'regular' line at least once, despite the wait time, to see ALL the theming; later, you can use the FastPass line or even the single riders line). When you get to the loading area, she will be directed or escorted to the exit platform.
Splash Mountain - you will, unfortunately, NOT get to experience the entire queue decor, because it involves stairs. Check with the Greeter for boarding instructions, since your wife will not be riding.