I use various passive ear plugs (Flint/Mack/Pro Ears).
The PE's are more expensive @ $10-$15/pair, but she really needs to try them for comfort as well as sound blocking function.
Some sizes of the foam plugs slip out of my ears, some larger ones are uncomfortable after a while and our cats like to squirrel away the corded PE's when I lay them on the bedside table.
I wear them for migraine and to reduce TV SPL's when my wife watches @ night (only TV is @ the foot of our bed).
I find all the cheap ones to be about the same sound wise (maybe minus 25-30 db) with a TV putting out 80bB+, but I rarely wear them in public as I tend to stay home with headaches.
Seems that the foam ones I used in the late 60's/70's/80's performed better than what is currently available, but perhaps I'm just getting more crotchaty.
DeKay