In reply to J1234:
It depends what you mean by "exposed". If your wife is frightened of actually falling, the walkways are pretty safe and well railed in. However if she simply doesn't like looking down from heights the walkway itself is probably best avoided as the stairways cross an overhanging cliff.
Either way it's much more exposed than the Cares Gorge - but if you have the head for it it's a stunning experience even for climbers.