that's good advice in life/business, perhaps....but dating you can't be like that. You can't be the nice guy....every jerk or no bs guy now, was prob one time a nice guy.
This older black dude at my gym told me, "don't be afraid to fire they(women) ass....b/c they'll fire you in a heartbeat if another dude is avaliable"
And to be honest, if ur a nice guy, every female is not worthy of being your friend.
She might be telling you one thing, while shes driving on the way to another dudes house. You're playing ourself if you keep being "friends" with her after she turned you down. We've all done it though

at least once