How long does grief last?
Grief has no fixed endpoint, and missing someone can last a lifetime without being a problem. For most bereaved people, the acute, disabling intensity softens substantially across the first year while waves continue around reminders. When intense daily yearning and real functional impairment persist beyond about a year, clinicians call it prolonged grief, and it is treatable.
The honest answer has two halves, and both matter. The first half: love does not have an expiry date, and neither does missing someone. People speak of a parent thirty years gone with tears in their eyes and full lives around them. That is not unresolved grief. That is what it looks like to have loved someone.
What typically changes over the first year
Early grief is often physical and totalizing: sleep breaks, appetite goes strange, concentration scatters, and the fact of the death has to be re-learned each morning. Across months, for most people, the volume comes down unevenly. Longitudinal studies find most bereaved people regain day-to-day functioning well within the first year while still experiencing real waves of grief, particularly at anniversaries, birthdays, and unguarded moments in supermarket aisles.
The waves themselves do not mean you are back at the beginning. A useful image from the research: early on, grief is the sea you are in; over time, it becomes weather that passes through a life you are living again.
When grief is worth treating
For a significant minority, roughly one in ten bereaved adults in some studies, grief stays at storm intensity. Both major diagnostic systems now describe this: ICD-11 calls it Prolonged Grief Disorder, marked by persistent longing or preoccupation with intense emotional pain and impairment lasting well beyond cultural norms; DSM-5-TR sets the marker for adults at twelve months, with intense yearning most days plus symptoms like identity disruption, disbelief, and inability to re-engage with life.
The reason to know this is hope, not labels: grief-specific therapies, such as the treatment developed by Katherine Shear and colleagues and tested in randomized trials, help most people who receive them. If you are past a year and grief still runs your days, that is not a personal failing to push through alone. It is a treatable condition with a good prognosis.
References: WHO ICD-11 (6B42). American Psychiatric Association, DSM-5-TR (2022). Shear et al. (2005) JAMA 293(21); Shear et al. (2014) JAMA Psychiatry 71(11). Bonanno et al., trajectory studies of bereavement.