This is a great question. I have a history of fearing failure/sabotaging my success. Two examples: I became passionate about the workshops in Theatre Techniques in Education that I had worked with in college, kind of ancillary to my theatre degree. I decided that my life's work was going to go to classrooms and teach teachers how to inject improvisation and creativity into their classrooms.
So the month after I graduated, I got a call from the guru of this area of study offering me a job as an intern with her group. I turned her job and instead worked as an office girl in a dark, dank warehouse!!!
Example Two: Working for NBC in New York, I decided to take advantage of their tuition reimbursement benefit and apply for a Masters in Broadcast Journalism at NYU. I was accepted, but never went, using my impending wedding as an excuse!!!
I count those two instances in my life as regrets that I have--regrets about my fear of failure short-circuiting my hopes and dreams. I did get over it, but hard lessons learned.
So.. today.. what would I do if I couldn't fail? Now, for me, the question is, what would I do if I could wipe away my debt--because now it's the debt that keeps me handcuffed, not fear of failure. So in that case, I would not work anymore, but I would travel the country and maybe write about permaculture topics and profile people working in it.
Debt aside, the money devil on my shoulder says "You want to send your grandkids to college" and "you want to have a house on the lake in Vermont" and "You want to be able to support causes" and "You don't want to have to worry about money like you used to" So each of those murmurings is a turn in the screws on my handcuffs.
I would think it would be the parent's job to help their kids go to college... not grandparents. Your main focus (IMO) now is retirement.