Where's the user-friendly text system?

My wife just called me - all up in rage. She just lost two hours of work. We are using Groove extensivly to distribute documents between ourselves and the different locations (at home, in the office, on the various laptops) we are using. After she had worked on a document in Word that she had opened from Groove she saved it. Groove detects the changes and asks you if you want to save the change to Groove as well. Now by mistake, she said “No” - and presto - everything was lost. Of course it’s easy to blame everything on the user. “You didn’t read the message when you clicked on No, so it’s all your fault”. But is it really that easy? Jef Raskin stipulates in his book The Humane Interface that computers should treat the users input as sacred - never putting it in jeopardy. That means, that a computer can undelete deletions at all times. To restore things, even - or maybe - in spite of - the user making the wrong decision about which button to press. We are humans, we make mistakes. So the question: Which programs are humane? Which text editor has unlimited undo/redo - even across sessions? What environement already has these features? Do you have any suggestions?