I learned many years ago not to loan my tools, as I have had the same experience as many of you, but I recently discovered something. I have two special electrician's screwdrivers which are purposely bent in kind of a Z shape, and the shafts freely rotate inside the handles. They were made by Klein, if anyone wants one. Most people think someone broke them when they first see them, but they are great for kind of hand cranking screws in and out of electrical boxes, etc. by just a rotating wiggle of your wrist. No batteries to go dead, like when using electric screwdrivers, and the wrist action to run them is very normal and non tiring.
Now, when someone asks me to borrow one of my tools, I just pull one of these screwdrivers out and show it to them while making the statement "I don't loan tools any more". They have never seen a screwdriver like one of these, so they think it's broken, and it's been very effective. I'm not lying because I won't loan tools to anyone except my sons, and even they are not allowed to borrow some of my tools, but just the sight of one of these screwdrivers, along with my statement, is enough to make people back off. If they are a very close friend, I'll loan a tool if I go with it to operate it, but they need to be a very close friend or this doesn't happen either.
I have acquired a lot of hand and power tools in my lifetime. All are about the best quality that were available at the time that I bought them, and my wife has never interfered with any of my tool purchases. But I have always made certain that food was on the table, my family was kept healthy and well clothed, and we all lived a comfortable life. When I bought tools, it was always done with money that did not affect the quality of their life if I spent it.
Some years after our marriage, my wife admitted to me that one of the reasons why she married me was because "I could fix anything". I've always said that "machines hate her" because she seems to always have trouble running machines, that no one else has any trouble running. She has trouble with the very basic un-smart cell phone that she has been using for over 10 years, when she needs to do anything more than answer it or make a call with it. Returning a missed call is always a problem. She's very smart about many things, but has some kind of "mental block" when she needs to run a machine. I laugh at her frequently when she has these problems, because just a push of a button or two is usually all that's needed.
Charley