Its not like they intended to kill her. If I gave you a knife and you stab yourself with it, should I be made to pay for that? Plus should we now stop radio pranks now because of this "one" case. I used to love listening to radio pranks with Steve Penk (a radio DJ in the UK) and he was awesome and I would still love and laugh at it now, the last thing we needs to go all PC about stuff for what happened to one unstable person. The only crime committed here is the suicide since last I checked that was a crime.
There's nothing that suggests she commited suicide over this.
In fact, the article states (even though the information is probably invalid since... Well; everyone would say they were in full support of the one who's now dead) that the hospital supported her, and that the royal family supported the nurses at the hospital.
Simply put: There's no evidence that suggests that the two incidents, the prank call and the nurse's death, are related. In fact, at this moment in time, 'prank call causes nurse's death' is nothing more than a causal story that is invented in order to make sense out of the nurse's death.
Here's a thing: Let's say the nurse had a really good friend who became very, very ill. A week later, the nurse offs herself. The title headline would say: 'Friend's illness causes nurse's suicide.' Or something along the line. In any case, that's what you would believe, because all you get for information is 'Friend is severely ill, nurse kills herself.'
That's like saying 'Nurse buys a blue ford fiesta with a broken exhaust. She kills herself a week later' and expecting the blue fiesta with broken exhaust to somehow be responsible for the nurse's death.