Trust is an important part of friendship, a less intense relationship than romantic love and marriage,
but also of great importance to people's satisfaction with their lives. There is a strong correlation
between social isolation and diminished well-being. The brain processes involved in interpersonal
bonding have much overlap with those identified for romantic and familial attachments. Spending
time with friends is highly pleasurable, involving dopamine brain circuitry. With good friends, you
feel a real bond and know that you can trust them to look out for your interests, so it is plausible that
oxytocin is involved as well