This is so very true.....we lost Simon our tuxedo cat May 2014 and Sebastian our Chantilly Nov. 2015, and the personalities of those two were just incredible; we love all our cats but those two were just such characters and were with us a long time, and they made such an impact on me that 6 months ago I found a cat in bad shape, Sylvester who look-wise is a 50-50 blend of the two of them, you couldn't sit down and design a cat any better than one who reminds us of both these great boys but he is his own personality and is just my joy, I pick him up and kiss him on the top of his head and whisper "I love you....I helped you and you helped me" so yes you are correct, some make a bigger impact on us than others. He is not a replacement, just a gentle reminder and a great tribute to those two special boys!
They are all special to us, but some leave a bigger hole in our lives than others. I'm sorry you lost your Mickey and I'm sorry you still miss him so very much. I miss all of mine who have passed, but there is 2 in particular who stole my heart in a whole other way and the pain of losing them seems...........a little bigger.
But they were as Mickey was "one of a kind", and the bond was and always will be so very strong between you and he. It is like in a small way he is still with you. I certainly can understand how you feel and why you still are so very upset, it is because the bond and the love was so strong between you....I wish you peace, and remember he is fine now, no problems, they ALL are fine, doing better than we are in fact lol!!! And you WILL see him again and he will tell you "I love you, THANK YOU for taking care of me!!!"