I love mine too it has not worn off at all I use it every single day and especially at night to read in bed with no lights on. I have a library full of books on it and I have only paid for 2, amazing how many good new books you can find for free if you are diligent about checking often for new ones.
You can find out about how to do the library loans here
How To Get Free eBooks From Libraries Using Overdrive
I still have not gone to get a library card here yet. And the pdn does have the Adobe Digital Rights it has an icon in the bottom bar for that.

If you are just going to read and not be using it to go online go to settings and network and have it turn off the wifi the battery will last much much longer, I only do the wifi when I use it to surf online, and also making sure you have it fully turned off and not just hibernate will save battery, to fully turn off pull and hold the off on switch to a count of 4 then release and the power off dialog box will appear if that does not show up you only put it in hibernate.
I leave mine plugged in on my side table when not in use so that it is always ready to go with a full charge and I rarely run low even when I read for a long time.

Glad you are enjoying it!