Defense against the future
Presence is your defense against the future and the past. Neither is happening now, but both somehow feel important enough to obsess over, especially in what would otherwise be a quiet and therefore wonderful moment, like the time right before you fall asleep, or when you’re showering. Obsession is never healthy, and when it gets in the way of peace it’s doing active damage.
Deliberate presence once a day is enough to form the habit, and let your brain know it doesn’t have to get caught up in the cycle. All you need is a reminder.