Answer:
dopamine
Step-by-step explanation:
The dopamine is a key neurotransmitter, usuallly triggerred by falling in love. The dopamine is responsible for making us feel the pleasure and the satisfaction associated when meeting someone we like, and this stimulus is reinforced as later contact will making to stay with the loved a rewarding experience.
Dopamine is always present in any activity that has reinforcement or feeling and need of "closing a cycle", the love hormone dopamine can have similar effects on the brain as with using drugs.
Sometimes love can directly influence health.
Other functions of dopamine feelings of contentment, calmness, and security, engagement needed for mate bonding.
Dopamine usually is present with other popular hormones like oxytocin
estrogen and testosterone. Together with hormones, like adrenaline, make body functions available for mating , like the classical experience when meeting someone we like will make our heart beat faster.