Sorry to hear about your loss.
My brother and I each have a cat in our house, they're still young so I know hopefully I'll have a lot of good times with them in the years to come, but I also know that one day that dreaded time will come where I have to say goodbye. I've had 2 or 3 other cats that I've had to part with in the past (1 lost in a blizzard, 1 hit by a car, and another of old age), so hopefully I'm more accustomed to the grieving process.
Time will heal your pain.