Dealing with loss-induced denial

Enough has passed now.

Some 14-15 months ago, I decided to finally set up the PC that was my New Year's present to myself.

My previous PC was seven years old already, but it was chock-full of all kind of useful data I had accumulated over those years, and I really wanted to transfer all of it (if possible) to my new silicon beastie. So, I bought an external hard disk, but due to the poorly aged hardware and software that my old PC had, it was a real hassle. First of all, the USB cable I got with the disk was too short. Second of all, really big files had to be split into archives in order for me to transfer them, but my hard drive was already filled to the brim, so I had to cut some data and paste it directly to the external disk in order to make space for all the archiving.

Now, here's the bit that's actually related to chess: the stuff that I decided to just cut and paste was some 40+ gigs of chess books, videos and other tutorials, because to me, they were the most important of all of my data, so I wanted to transfer them as soon as possible, just in case.

But alas, in a cruel twist of irony, that short USB cable I had mentioned... had accidentally plugged out during one too many transfers prior to that, so while I was copying some games or something after having finished with the chess material, one final plugout was enough to send the disk over the edge. Due to initialisation problems, it could not read anything anymore, so I had to turn it in and was sent a new one, but all of my chess data... ALL OF IT... was completely lost.

And to make it worse, I hadn't actually set up my new PC at the time, because it was too much of a hassle to repetitively plug and unplug almost all of the cables from one computer to another, so there was no chance of saving the chess data anywhere.

At first, I was like "well, I didn't really use each and every book or video that I got, and not only that, but it's also time for me to play more and study less", and it worked... for a while. Then my playing strength took a slow but rather persistent dive over the next year, and every time I wanted to check (hehe) my chess knowledge and understanding with WHATEVER, I remembered that I didn't have that whatever at my disposal anymore. I even remember which books and videos were the most beneficial to me, both general and phase-specific (but still not many of them, 10 tops if one doesn't count openings), but I can't even find those again for the life of me.

So, what could I do? What SHOULD I do at this point? I want to get better at chess again, but so many websites I collected the materials from are currently dead, and coaching is expensive. Thank you in advance.

BTW, the OP's pretty TL;DR-ish, so just skip to the last big paragraph if you see no point in semi-melodramatic introductions. xD