Losing a Pet is Like Losing any Loved One
Anyone who has allowed a pet to become a part of their life understands that a pet is a member of your family. When you lose that pet, whether unexpectedly or from old age, it does not change the fact that a hole has been left in your life. You still need to take the time to grieve your loss until someday, you feel able to celebrate your pet's life.
Unfortunately, many people do not understand your grief, and their lack of understanding may cause them to inadvertently hurt you further. They may do this by acting as though the pet never existed and your grief is not real, or by making the suggestion that it was just a dog, cat, ferret, or whatever and can be replaced.
If you've ever loved a pet, you know that they cannot "just be replaced", much like a person cannot be replaced. I'd like to offer some suggestions that may help you in your grieving process: