Sweetie, you cry all you need to, it helps, and is natures way...you are still grieving, and don't be afraid to do it..It is all part of the healing process..when I lost Poppy I cried for weeks (still do it occasionally even now, especially when I am touched by a particular post like yours, and it brings back the memory of her suffering)...my eyes were so swollen I looked like a bullfrog!.....After the vet came to our home to help her to the bridge, We took off that same day to our chalet at the coast, because I couldn't bear to be at home without her..I took her collar with me, and her pillow, so I could still smell her, and I too was in bits and frightened to return home.
Of course eventually we had to come back, and it was hard...so hard..she wasn't there to greet me with her usual nutty Boxer dance and kisses, and It didn't seem like home anymore...but it had to be done.
My heart goes out to you, take one day at a time...cry,remember all the happy times you had with Cooper..but above all remember what a lucky boy he was to have had a wonderful mum like you to care for him.xx