While it's true that everyone goes through this, it's not the same for everyone. It's not even always the same for one person with different bereavements.
I've lost both parents. One I was close to and one I didn't really know. My grief experience was different with each.
For me it took a long time and lots of counselling to get through my grief about losing my mum - it was among the two biggest heartbreaks of my entire life - and although my partner has been amazingly supportive there are others who just didn't get why it hit me so hard.
Grief is unique and extremely varied in its expression, how long it takes, and how hard it hits you. Take it from me, you have my endless sympathy.
Your partner is being unfair and insensitive, but this may be because he just hasn't experienced it liked you have (or at all).
What you could do, is try to find a resource that explains grief and ask him to read it. Tell him you need his support and tell him that mostly means a quiet listening ear and a cuddle. He may not know what to say, and he may feel helpless about that, but the best thing he can do is just bear witness and offer his loving hugs.
I send you hugs through the internet as well as flowers. You will get through this but don't absorb anyone else's ideas about how and when. Do get counselling if you need (and don't be afraid to shop around until you find the right counsellor), or if that's not for you, you can find books on self care during bereavement too.
