The Bible really only gives three different ways a man ought to relate to women: mothers, sisters, and a wife. Paul exhorts men to treat "older women as mothers, younger women as sisters, in all purity" (1 Timothy 5:2).
Men, you may notice that there is no category of "potentials" or "neutrals." If they are not your wife, then they are your mother or sister in Christ, that's it. And so for all men (especially single men), you need to treat the young women around you as you would treat your very own sister.
Normally, 1 Timothy 5:2 is used by leaders with the intent to keep men from lusting after the women in the church and from messing around with them sexually. Most of the conversations take place like this:
Youth pastor: You would never undress your sister with your eyes, right?
Young men: Gross!
Youth pastor: You would never make-out with your sister and so hinder her walk with God, right?
Young men: That's so wrong on so many levels!
Youth pastor: That's what happens when you lust after or commit sexual acts with your sisters in Christ.
(All the young men shudder in fear)
It is great to pursue purity and that is definitely one of the desired effects of Paul's writing to Timothy, but too many men miss the big picture that Paul is trying to communicate.
Instead, they overcompensate.
When they interact with a woman, eyes are on the ground or sky—it's "Hi. Bye."—and then back to business. Heaven forbid that they have a conversation with a woman. Their fear of being smitten (or smote) by God—as opposed to being smitten with a woman—ends up manifesting itself as awkwardness and cowardice. They possess the right heart to avoid sin but the end result is a very selfish attitude.
This is not how real brothers treat real sisters.
A real brother not only treats his sister with all manner of purity but loves her at the same time. He loves her through seeking her highest good. He talks to her. He protects her. He encourages her. He builds her up. He has a friendship with her. He serves her. He sets an example for her. He points her towards Christ.
A good brother isn't consumed with fears of sinning with or against his sister. He really doesn't think about himself at all. He simply—and purely—finds joy in giving his sister the best.
Translate this over to the church. Christian men, both married and single, need to realize that we have been adopted into a family that in many ways is more real than even our earthly family. Because of that, we have a lot of sisters.
Yes, these sisters need us to treat them purely, but it needs to be so much more than that. A Christian man should be able to seek the best for every Christian woman he encounters. He should be able to love her as Christ loves her.
Instead of walking around thinking about baseball stats to push out impure thoughts, Christian men should focus on protecting those women. We should care for them, encourage them, have friendships with them, and serve them. No ulterior motives. No seeking anything in return.
Doesn't mean you are the flirty guy. It doesn't mean you become best friends with every woman in the church. What is does mean is that you are committed as a man to protecting the spiritual well-being of the women of the church.
Now, that means different things for you with different women. Sometimes, you can be close friends. Sometimes, you need to keep your distance.
But don't be perverted, awkward, or afraid, instead ask yourself always, in every interaction, am I pointing her towards Christ?