Due to various details I'm not at liberty to go into at the moment, this is not something which will ever happen.
If you look at squishies, those are a one use item which break instantly and there are never any issues. Honestly, books are just like food and squishies with extra 'possible' uses.
There are a couple of options here:
1. Books remain the same.
2. Books get a single use without breaking, and after that, they can't be read to a pet, but can still be added to a library. This makes them useless for other pets and basically wastes their only 'intellect charge' but still count for libraries. This is the only way they will ever have a 'break timer' or anything stating when they will break, we won't allow books to have multiple guaranteed charges.
3. Books change to be like food and squishies, and break instantly upon use. This gets rid of the mental issue people have here, which is 'my rare item MIGHT go away omg!' when in actuality, it should be treated as a one use item that you MIGHT gain extra uses from. This means that books are BETTER than food or squishies, yet we have those as leaderboard prizes and in CS packs etc all the time without anyone complaining.
The issue is, books can never be infinite use or they would be loaned out like an RRay and become absolutely worthless. That doesn't fit in with our future plans of the site.
If anyone would like to suggest another alternative method such as one I mentioned above that doesn't involve infinite use books, feel free to; or let me know what you think of the options I listed.