As someone who is suffering from a spot of Black Dog at the moment I can assure you it's not a nice place.
There was an earlier post that mentioned people who are suited and booted and on their way to work who suddenly decide just to jump in front of a train. They didn't plan to. Something clicks -
"silicon chip within her brain,
goes into overdrive"
and they do it.
My speculation only, a sudden psychotic episode may have happened here.