the interest rate of a bond isn't just "liquidity/the time value of money", it also contains expectations for future inflation rates. However, we never know the future, so inflation risk cannot be eliminated/hedged by any means, so being "wrong" about the future might harm or reward you.
furthermore, by portfolio theory, you would have needed to reinvest all the interest received from this bond immediately upon receipt as part of your evaluation of the performance of the bond (which, that being difficult to do is why we evaluate bonds at "present value"). All those past interest payments made would have been reinvested at prevailing (e.g. so-called "inflationary") rates and might have done extraordinarily well.
If you include all factors, this bond might have been the best investment she could have made, and it would be wrong to describe it as somehow "ravaged by inflation"; with nothing any better to do with her savings, it's the idea that money is somehow "fixed" and potentially permanent unless "eroded" that we should see as damaged, not the value of this bond.