When you lose someone you love, your whole world is shattered. Nothing looks the same. People don't know what to say and the only solace can be found in moments of exhausted sleep. You're not supposed to forget them. You're not supposed to get over it or even through it.
That life you had will not come back. You will see them again one day. In the meantime, you've got this life to live. It won't be the same, but it doesn't have to be awful. If you'd passed instead of them, you wouldn't want to be looking down seeing their days filled with misery mourning the loss of you. Grieve, yes, and mourn, and don't rush the flood of feelings and memories.
But when you feel you can begin again, do so without guilt. Live for them, love for them, share every good thing they taught you with the whole world. This is a beautiful way to honor their life and have what they gave to you carry on in spirit for the rest of your days.