My tag line says, “The reason I have what you want is, I never loaned it out before.”
If someone wants to use our tools, we should be up front about replacement of tools damaged by abuse, neglect or loss.
That said, while other people were buying things for themselves, be it skis, a new shotgun or what have you, my money went to my tools. As such, it’s okay to be selfish with them, just as they would be about lending you their skis, shotgun or other item you don’t have.
If I destroyed someone’s tool, it’s on me. That does not mean replacing a Porter Cable framing gun with a Harbor Freight version.
All that aside, this could be counted as a lesson, but it wouldn’t be unreasonable to ask her to cover the cost of new Velco you have to, like Brian said, glue on in place of the old. I keep a stack of the foam pads for my several 1/4 pad sanders just because I know they die too.
NOW, if it were my Festool, I’d want the money for the replacement. After all, for the $20.00-$40.00 bucks, those I allow in my shop usually don’t get pinged for sandpaper (a sheet or a disk runs a buck, even in quantity) heat, air, electric, tool wear, blade wear, etc. Many times, they get free wood. Pretty cheap rent, in my opinion.