You're a great friend. I haven't quite managed to lend out my wool and let it out of my sight... I was kayak touring with a friend recently and let her borrow a lot of my kayaking clothing and equipment... I still cringed everytime I heard her whack my carbon fiber paddle with something.

I lent my sister a bunch of outdoor gear recently so she & her daughter could go tubing... A way long time ago she shrunk one of my wool sweaters, so I didn't let her borrow any wool, but let them both borrow down jackets, goretex shells and pants, etc. I was having nightmares of her washing my down jackets (thankfully she didn't!) or ripping some goretex. I'm sure it's all brands that she's never heard of, so she doesn't quite understand how expensive the stuff I was lending her really was, and I didn't want to be that person who lends you something and harps on how expensive and what it is, to the extent that you don't want to borrow it or use it anymore.