When we grieve, you need to be able to divide or distract yourself. Nobody can mourn around the clock – it's too painful. So don't judge yourself for throwing yourself into work, a Netflix binge, a bottle of wine, or the arms of a rebound.
Just know that at some point you have to feel yourself in order to heal. You can just see it as productive "work" necessary to get to the other side. I recommend writing journals, listening to music, creating art, speaking to a therapist and penetrating your body as there is grief there: yoga, dance, walking, acupuncture and massage are some that have really helped me with this time .