What is the role of secrecy in Charlie's life?

Charlie keeps secrets for other people: Patrick's homosexual relationship, his father's crying, his sister's abortion, his sister's abusive relationship, and own his childhood sexual abuse. In some cases, secrets bring Charlie closer to other people; this is very much the case when he drives his sister to the abortion clinic and when he keeps Patrick's relationship a secret. In other cases, the secrets tear him down - for instance, when he conceals his own sexual abuse.