I tell this story to illustrate her misunderstanding as I doubt this type of story is unique. While her comment that none are perfect rings of humility and non-judgmentalism, I believe it is a betrays incorrect thinking. A correct understanding of salvation helps avoid this.
As I have previously written, the nature of salvation is not about a set of right beliefs or pronouncement of a creed. A discipleship is a follower. That is, we repent (turn around) and start following Jesus. This is why taking a snapshot of people can make it hard to see who is and who is not a Christian. It is not where we are on the road, it is what direction we are walking in. You can't tell by glancing at the tree, you need to see the fruit, and fruit takes time to develop.
This side of perfection we all sin, so the pastor's wife is correct in this regard. The issue is followers who stumble get up and keep walking (with the help of Christ). It is not the falling that defines us, it is the following. Where pastor's wife goes wrong is she is aligning her faltering with the music leader's turning away. Choosing to deliberately live in a way we know God opposes, with no attempt not live this way, is not the behaviour of one following Christ, it is the behaviour of one refusing to look at him. This is not necessarily apostasy, but it is placing oneself in a dangerous position.
He who is often reproved, yet stiffens his neck,/I will add that positions of leadership in the church carry a great responsibility and there may be acts of sin that demand you step down, at least for a time, for the sake of the body. This sin may happen in the context of a person attempting to follow Jesus; this is not what I am addressing here.
will suddenly be broken beyond healing. (Proverbs 29:1)