Touch, music, and exercise can release oxytocin, which can help us bond with loved ones.
The pituitary gland releases oxytocin, a hormone, into the bloodstream from the hypothalamus. One of the reasons it is referred to as the "love drug" or "love hormone" is that one of its primary functions is to facilitate childbirth.

Oxytocin makes the uterine muscles contract and increases the production of prostaglandins, which also make the uterine muscles contract. Oxytocin can sometimes be given to women whose labor is taking too long to progress. Oxytocin helps to bond mother and child after the baby is born by moving milk from the breast ducts to the nipple.

When we are in love and are excited by our sexual partner, our bodies also produce oxytocin. It has been dubbed "love hormone" and "cuddle hormone" as a result.