Breakups
After a breakup, the mind often tries to solve the relationship retroactively, what you missed, what you should have said, whether it could have worked.
Grief is not linear. You may miss someone you know you should not return to, feel angry, feel numb, or feel embarrassed by how long it is taking.
Breakups also reveal habits: who you become in partnership, what you tolerate, and what you fear about being alone. Grief does not need a silver lining, and contact does not need an immediate decision.