Is it possible that your dh is pushing so hard because he needs another to help with his grief? I really understand that you need more time, as I went through similar when I lost my Rebel Cat. She was 18 years old and passed away right after Christmas 2006. I still have not been able to adopt a new cat and the thought of doing so is no easier today than it was a year ago.
Everyone's grieving process is unique unto them, but when there are others who are grieving together the process becomes more complex. I hope you and your husband find the balance needed to help you both through your pain. God bless......
