First and foremost losing a pet IS a great strain... whether it be a dog, cat, eel or rat. As humans we tend to humanise the animals around us (there's a word for it... it slips my mind... your challenge if you wish to accept it I guess!

) so to lose them is like losing a friend or even a family member.
Everyone deals with loss in a different way... some of us like bounce back after a day or so... others feel the need to weep readily for months after... not one way of coping with death is right or wrong. Eventually the pain will subside though... sharing your thoughts, pain and feelings is the first step to healing... don't be ashamed of feeling the way you do, you are not alone.
I really believe that those we are close to can still be with us for the rest of our lives... we can "feel" their presence. I'm unsure whether this is their spirit or ghost or whether its just situations reminding us of them but either way... those kinds of comforts are sometimes very important in recovery