I'm so sorry that you are suffering! You are entitled to grieve, you are entitled to take as long as you need to do so.

I can't give you any advice, even if I could, it probably wouldn't change how you are feeling, but know that your son is a gift. If anything, there isn't a hole, he will always be your son, and you will always feel love for him! What he did was make your capacity to love so much bigger and stronger and made room for ANOTHER baby to be loved.