Well, they can live long is you take good care of them. Clean them out regulary ect. I had a goldfish called Mobey and he lived for 9 years his tail was really big lol. I really never thought he would live long because i got him from a carnivl on hoo...

So sorry bout your loss. That so called friend wouldn't be my friend anymore. Although they are just rodents you can get atached to them like glue. I have a golden syrian hamster named toby and i would be so upset...