Grief is an enormously complicated emotional state that cannot be pithily summed up like that sentence. It's just a quote from a game.
In my experience, it doesn't pass, as in disappear. Instead, the fact of the loss slowly becomes a new fact of your reality. The newness of it will pass. The rawness of the pain will fade - most of the time. There will always be things that bring the person right back sitting next to you. But you begin to re-make your life.
If you continue to struggle and haven't already done so, I can recommend talking with a counselor (I hate the word therapist). Sometimes we just need to unload, but don't want to unload on/burden the other people in our life. Grief can be isolating in this way.
I feel the same way - at least once a week I think to myself, I should tell my mom about something her grandchildren did, and then I remember she's not here any more.
