My BFF just lost her two year old cat to lymphoma. She and her niece had hand raised Peter Pan from an abandoned hour old newborn still attached to his dead siblings and placenta found on their porch. It has been a particularly wrenching loss for them and me.
Also, I am right now trying to ease one of my rescue cats, Rosie, into crossing the Bridge. Apparently, as a kitten/young cat, she only got one dose of vaccine for rhinotracheitis instead of the three doses recommended, and when she escaped from the house during the delivery of my new refrigerator, she became infected with the virus. Rosie now has a chronic infection with the virus. She is 14 and it is just a matter of time before it kills her.
Last year, I lost my heartcat to heart disease and I miss Timmy (14 years) so much still... The year before it was Maxx (15 years) with his severe asthma and COPD. All my cats are over ten years old now and I know I will lose them, one by one. But having them in my life is so rewarding for so many years, I will deal with the parting and count myself lucky for the enrichment they have brought to me.