As I have observed before on AB, the minute we start to care for anyone or anything, there is pain at the end of it somewhere. That is part of the commitment we make when we decide to live with our pets.
Of course, knowing that rationally does nothing heal the emotional pain of loss - that is something that has to be endured without relief or short-cuts - only with the knowledge that time does heal, but again, that really doesn't help in these early days.
Don't try and fight your feelings. Remember your friend with love and affection, and know that he is not in pain, and that he loved you as you loved him.
I think having a little talk from time to time - especially to sympathetic ears which you find here, is a good thing to do. It gets your thoughts and memories in order, and helps to come to terms with the fact that althoug he is gone, he remains a big part of your life, which is as it should be.
In time the pain will receed, but the good memories will always remain. You wil forget the tears over his loss, but remember the fun you had with him, and he had with you.