Fairly recently, my sister had to put down one of her cats and it is still hard to come to terms with. The cat was very friendly and a bit of a troublemaker but we loved him. He was only 1.5 years old. Since then, I have had trouble getting any sleep. Before I can go to sleep, my mind flashes back to the fact that he is no longer here, preventing me from getting a good sleep. I miss him deeply, even though he was not mine. I want to move forward but it is just so hard to forget about him and what fun it was to have him running around with his friend.
I am sorry to hear about the loss of your beloved pet, but the truth is that you can’t do anything about it. You can honor him and cherish good times with him, but it is in the past, and now you must try to recover. Time heals everything. In the meantime, maybe take NyQuil to help you sleep. Rest in peace.