First you will feel shock and/or denial. The feeling of numbness can last hours to weeks. This period is often described as "unreal", (i.e. being amazed to have made it through a euthanasia). Some reactions people experince during this stage are: having disorganized thoughts, feeling unaffected, thinking about suicide, feeling numb, being euphoric or hysterical, feeling outside their body, or being talkative, hyper or passive. Other people may feel denial of the loss. (i.e. "I can't believe he is really gone...it just doesn't seem real.)
You will begin to feel yearning. People will often find themselves acutely missing the pet that is gone. Individuals in this phase can be pre-occupied with thoughts of the deceased; they may have dreams about the pet who is gone. Reactions experienced may also include sensing that one sees or hears the pet outside their home. Feelings commonly experienced are intense sadness, fear, anger, relief, irritability, guilt and yearning. Sometimes anger is not directed at the loss, but instead towards a family member, veterinarian, at themselves or God. During this period you may find yourself bursting into tears at unexpected times. People may also experience physical illness, pain, weight change, fatigue and change in appetite.
You will begin to feel disorganized. During this phase you beginning to live your life without your feline companion and learning new routines. This commonly leads to feeling disorganized, as well as needing to evaluate and learn different ways of managing life (i.e. how to fill that empty spot when coming home without someone to greet you).
Slowly you will reorganize your life. People in grief forget that grief is a process and during this process new coping skills are learned. The pet who is gone is usually never forgotten. In the case of death, most people never fully "get over" the loss. Survivors learn to live with loss. The intensity of the loss changes, and a survivor can rejoin life. At this point you find that you begin to slowly return to life as normal as possible with what you have gone through. Individuals may establish new relationships with pets. Sadness and crying still occur at times, while simultaneously increased happiness will be experienced.
Be easy on yourself and know that all people deal with loss in their own way. If you have a friend dealing with pet loss, please be there for them and most importantly listen, sometimes we just need someone to listen to how we are feeling.