Why is Grief so exhausting?
Many grievers are caught off guard by how physically exhausting grief feels. They expect sadness. They do not expect a body that feels heavy, a mind that feels foggy, and an energy level that feels depleted no matter how much they sleep. I hear this in my office frequently. I like to give them a metaphor. Imagine that you just lost a limb, we’ll say your arm. You need time to heal because your body just lost a major part of itself. It’s having to heal but also learn how to navigate without an arm, something you used to have and grew accustomed to naturally. Everyone sees the loss of a limb because it’s outside your body. When you lose a loved one the healing that needs to take place is inner work and not visible in the same way as losing a limb.
Grief is exhausting because it is not only emotional. It is biological.
When you lose someone you love, your brain and nervous system go into a prolonged state of stress response. Your body releases stress hormones, activates immune responses, and increases inflammation. These processes are meant to help you survive threats. But in grief, the “threat” is ongoing. The loss does not resolve. The nervous system continues to register absence, danger, and change.
Mary-Frances O’Connor’s research shows that each time the brain is confronted with the reality that your loved one is gone, it mobilizes resources to process that absence. Over and over again, your system is asked to update reality. That repeated effort takes enormous energy. She has two amazing books on this topic The Grieving Body and The Grieving Brain.
This is why grief can feel like running a marathon while standing still.
Fatigue in grief can look like:
Needing more sleep but not feeling rested
Brain fog and difficulty concentrating
Heavy limbs or body aches
Lower tolerance for stress
Reduced motivation
Increased need for downtime
This is not laziness. This is not weakness. This is your body doing deep adaptive work.
Rest, hydration, nutrition, and gentleness are not optional in grief. They are part of treatment. When someone says, “I don’t know why I’m so tired,” the most honest answer is often: because your body is grieving too.