This could very well begin when we know the pet must be put down. We may say, He looks like he s getting better or Maybe, if we wait a bit longer, she ll heal completely . Denial could be as minor as dreaming our pet is still alive or as major as wholeheartedly believing our pet will come back. Denial is a natural part of the grieving process. There is nothing wrong with it unless it begins to interfere with everyday functioning.
Anger is a very explosive stage and is often the most damaging.
Anger is, however, natural. It could manifest as anger toward the vet, other pets, family members, yourself, or anyone within striking distance. There may be anger at the vet for putting the pet to sleep, anger at other pets that are still alive, just for being alive or even anger at the deceased pet for needing to be put to sleep. You may lash out at other family members for, as you perceive it, talking you into putting the pet to sleep. You could even feel anger at yourself for making the decision to put the pet to sleep.