We have a 'jumper'

I was with a crowd who were looking at a jumper on a building when this guy appeared next to me and asked, "What's going on? "

"A woman up there is threatening to jump, they have just sent a negotiator up to try and talk her down. "

"Oh God, that's my wife, " he said, and ran off.

"Where are you going? " I called.

Spoiler:

"to stop him, " he shouted.