Another thought: I wonder if all of these people who say that men and women should be trusted to be alone because nothing will happen, would also give away their user name and password to their bank account to anyone? I wouldn't trust just about anyone with mine. People are people and if tempted are likely to slip.
The sexual urge is no less powerful than the desire for money. It is actually far more powerful. So if we don't trust people with our private bank information, we shouldn't trust them to control the most powerful urge known to man.
אל תאמין בעצמך עד יום מותך.