If your self-esteem depends on a woman's behavior towards you, then it isn't self-esteem to begin with.
As a gal would you put up with a guy cancelling on you right before a planned date?
Would you give the guy a second chance?
Doubt it. And why? Because it’s all about respect. Someone cares enough to set up plans with you - you show up. If the guy cancels the first thought is this - “I guess he really wasn’t that interested anyways”.
Again - respect is not hard, treat people the way you would want to be treated.