I'm so sorry for your loss.
(((BIG HUG))) I lost my dad 4 years ago and still miss him a lot. The pain and sadness does get better with time, so just let yourself grieve. The main thing that helped me get through was my belief that he's in heaven and is happy there and that I will see him again someday.
Hang in there,
Dx'd Crohn's in '99 at age 28. Proctocolectomy and permanent ileostomy in '06.
Disease-free and medicine-free since surgery and very thankful to be healthy again.