Falling away decisions

I was thinking about backsliding today. I got to thinking about the choices someone makes as they slide further from their faith.

I wondered... What is the final straw?

Is it getting drunk? Taking drugs? Changing social circles? Having sex? Not feeling guilty about doing any (and more) of the above?

I haven't come to a conclusion... but i think having sex is a fair indicator. When you consciously decide to step over that threshold without reservation, i think it is a fair indicator where you stand with God.