I’m not sure I see a problem with that definition for disordered grief. To truly experience three of those every day one year on would be debilitating. Having the person pop into your thoughts regularly, forgetting they’re gone etc sounds like normal grief (which is also horrible but not debilitating). I guess I would look at it in the way that people feel depressed and then there are people that can’t get out of bed, keep themselves clean, or go to work. Both suck. One’s a serious clinical issue if it’s not improving.