What does the counselor mean by “you’re as sick as your secrets”?

This is a common expression used in meetings of Alcoholics Anonymous (AA) and other substance-abuse counseling groups. What it means is that one of the hallmarks of addiction is deception. Lies are regularly used by addicts to cover both their addictions and their actions. If they continue to be secretive and dishonest, if they hide from themselves and others the true extent of their addictions, then they will remain sick. Without honesty, there cannot be recovery.
In Evicted, Scott, a recovering drug addict, attends regular AA meetings, and this is where the expression is heard. Although he is determined to beat his addictions, Scott suffers a serious relapse when he learns that the AA and group therapy sessions he has been attending will not count toward regaining the nursing license he lost due to his drug problem.