Many unchurched people have trouble understanding Christians. We are, for example often accused of being hypocrites, but that is a lot like telling an alcoholic, that they are not one, because they attend AA. If we were perfect, we would not need to go to church.
While we are supposed to be getting better, we do fall off the wagon. There are people who have been sober for twenty years, that suddenly find themselves staring at an advertisement for their favorite poison. Christians can fall prey to their past sins as well, especially if they are facing tough situations in their own life.
We both have to admit to not being perfect
Christians and Alcoholics both ask a higher power to help us.
We both have to admit to being powerless against our sins.
We both need a person who is more mature in the organization who is willing to come pick us up and put us in the passenger seat when we are weak.
We both have many sins or mistakes that we have to admit to, and atone for if possible.
While not everyone has knowledge of a decent church, most of us have TVs and have seen characters on TV struggle with alcohol and attend AA meetings. So this general knowledge may help you explain it to others the next time someone calls Christians hypocrites.