Personally, even though it hit me straight away, it took me years to actually get over it.
I'd maybe suggest seeing your uni counselor, just to ramble on about exactly how you feel... Even if all you do is speak, it might help in the future. Also, to have someone who listens to you and doesn't judge you when you say what could seem the silliest of things, can be a really good way of 'getting over it', so to speak.
Also, how about Cruse Bereavement Care? I think they have a phone number, as well as trained counselors to talk to, specifically for the grieved.
Everyone grieves in their own way, and I'm very sorry for your loss <3
Time is a healer, but you might just be in a sort of shock over it all. Or maybe you might have been subconsciously getting yourself ready for it all along, and therefore it's not hit you as badly as it could have if it had been sudden.
Feel free to PM me, as a grieved person myself, I like to think I know a little on the subject. I also like to think that it happened to me so I can help others, which is generally what I try to do =)