Thank you for your kind words. We have actually had one of our cats die - our lovely black male cat Shadow died in 2010. He was only 7, so it was very unexpected, since he was quite young and seemed fine up until the last half an hour before he died. He died in the car on the way to the vets... The vet thought he'd had a stroke or a heart attack. I still miss him a lot. He was such a nice, friendly cat.
Smudge is our first and oldest cat (she was already an adult cat when we got her in 1998, so she's around 17 years old now). I didn't really expect her to live for that much longer, but I'd always hoped she'd die peacefully in her sleep when she's about 20, and not in pain like Shadow did. I really hope she'll be alright, but I can't help but not feel very optimistic about her future, since from what I've read most 'lumps' where she had it end up being cancerous 90% of the time. :(
Incidentally, here's a picture of Smudge. Isn't she a nice old lady? ^^ :
http://img.photobucket.com/albums/v94/Heliotrope1987/19thjune02_zps38ed43c4.jpg
You said you knew how I felt - so what happened to your cat?