I'll echo what others have said here: give grief space.
Try to remember mourning is a process rather than an event; i.e., some days you'll be feeling really listless, whereas other days it won't hurt as much.
Either way, acknowledging the emotion and stay with it is a good way to make peace in your inner turbulence. The more you loved, the more you'll hurt, I guess.
Sorry you have to go through this, my friend.