These two weaning experiences share a name but are fundamentally different processes. Understanding the differences helps you prepare for whichever one (or both) you're facing.
Weaning from the breast is a biological relationship ending. Your body has been producing milk in response to demand, regulated by prolactin and oxytocin. When nursing stops, those hormone levels drop — sometimes quickly enough to cause mood disturbances similar to PMS or postpartum mood changes. A 2018 review in Breastfeeding Medicine documented that some mothers experience significant sadness, irritability, or anxiety during weaning that is hormone-driven, not situational. On top of the hormones, there's the emotional layer: the nursing relationship is intimate, and its ending can feel like a loss even when the decision is welcome.
Weaning from the bottle is a habit change. The parent's body is not involved. The child is attached to the object and the routine — the feeling of the nipple, the position of being held with a bottle, the bedtime ritual. This is real attachment, but it's psychological, not hormonal. The transition is about replacing a comfort habit with a new routine, not managing biological withdrawal. Our sippy cup vs. open cup guide covers which vessel to replace the bottle with.