If you have a bonded pair, it is possible (but not always!) to lose one right after the other- it's heartbreaking, I've had it happen twice in the last 20 years. Much like people, they can grieve and feel loss. Both times when I lost the other mate, they were alone when the other one died, if there is another playmate in the house, they seem to do better.
If having another ferret isn't an option, just be sure to give the remaining carpet shark lots of attention and mental stimulation (ie time outside the cage). Also watch their diet and make sure they're still eating, if they stop and start to lose weight find food they like quick, or perhaps some duk soup. Get them to a vet in a couple of days if they won't take food.