Before you read and further, please know that I am not an expert on this topic and I certainly don't pretend to be, these are only my opinions.
So, in any conversation about the psychology of woman, girls especially, the idea that girls are far more emotional than men, is sure to be raised. Whether or not you agree with that, maybe it would be safer to assume that women have dissimilar emotions than men, or at least different ways of interpreting those emotions. There always seems to be a misunderstanding between the needs of both genders, and maybe that is because they have different ways of feeling certain things. How one guy might cope with a certain situation, might be radically different than how a girl might, what a girl might take for an insult might not have even crossed the mind of the guy. This isn't because anyone is better, they are just different. If girls respond to things with more of an emotional emphasis, that is not a negative thing, it's a psychological thing, and that psychosis is just the same as the one that creates the more instinctual emphasis in a man. But like I said, this is all psychological to me, mainly because I have seen guys act with more emphasis on emotion than the stereotypical instinct that they are supposed to. And psychology has a lot more to do with the mind, than the heart, or the gender. From there you could dive into many Freudian and Nietzsche like concepts, but I'll keep it simple, I think that how you are raised determines most of you are. Sure you can debate with a lot of minor details and quirks, but it is undeniable that what you experience as a child stays with you, in some form or another. So if this is the case, than if you were brought up with a specific set of influences, than you would develop as a person in a very specific way. Like if you were taught to be more predisposed to emotions, than you would develop into a very emotional person. And sense girls are the stereotypical figure of emotion, than parents would be more inclined to raise their female child as such. My point being is that I think most girls are far more emotional than guys.