I had one of my little girls not too long ago, one that I had refered to many times as my 'little puny one' in my posts. Her shell had a lot of wear on it from water being too acidic.
It was my fault that she got so bad off. I know that now. Though she already had a lot of damage from the pet store where I got her from and I'm sure that didn't help at all. Anyway, I thought she only had 1 hole in her shell. I was waiting for my supplies to get in so that I could patch that hole up.
I noticed that she had been just laying there for a couple days, but she was still moving her head around an moving her antennas too. So I knew she was alive and I never thought much of her just laying there because they do that every now and again. She was half out of her shell so I wasn't all that worried about her.
After day three I was a bit more concerned.
Several times I'd noticed the other snails over there 'cleaning her shell' and again... never thought anything of it. They do that to each other all the time.
On day four, she got turned where the uppermost spires of her shell were facing me and I realized what was going on.
Apparently on those uppermost spires, her shell was worn down so thin that the other snails just ate right through it. They had eaten a good deal of her soft tissue out and... it was in an area that she wouldn't die immediately, but with such a huge spot cleared out... she would die eventually.
What I did was crush her. It was the quickest and most certian way that I could think of. I've read all of the controversy about the freezing vs. not freezing here.... and I just wasn't sure. So... I smashed instead. I hated doing it. It was so hard for me because she was one of my very first 3 snails... but... she couldn't live like that. So, I felt that I had to. I'm sure it was better for her than being eaten alive until she finally died or just dieing slowly from the loss of what had already been eaten.
Anywho... that's my story.

Thanks, Erin.