The argument can also be made that blue hair is a way of taking back one's sense of self — as demonstrated by the celebs listed above, who were all experiencing shifts in their lives and careers pre-blueing. Experts say that when women find themselves defined by a certain aspect — specifically relationships — that dynamic shifts and it can lead to a desire to reclaim a separate identity and reinvent one's self.Dr. Erica Slotter , a social psychologist and assistant professor at Villanova University, notes that when involved in a romantic relationship, many women's sense of identity changes. "We tend to become more similar to our partners over time. We take on some of their characteristics and they take on some of ours. Essentially, we create a sense of ourselves within the context of the relationship. So, it follows that when a relationship ends, our sense of identity has to change again. Specifically, we have to renegotiate who we are in the absence of a partner who was influential in shaping us."Dr. Slotter says that the change to who you are after a breakup contributes to a reaction called self-concept clarity (SCC). "Low levels of SCC tend to predict emotional distress and poorer well-being. We find that after the end of a relationships, people feel that their identity is changing and this predicts them feeling less certain about who they are." So what better way to create your independent identity and start off on a new chapter of your life than by going balls to the wall with a unique, unexpected hair colour?Traditionally, when a woman was looking to reinvent herself or emotionally detach herself from a look, a change in hairstyle, with guidelines, of course, was the way to go. Not so anymore, says Houtenbos — the rules have been thrown out and it's the wild, wild west of hair. "The colour thing has nothing to do anymore with 'does it flatter me?' It's just about making an arbitrary choice that doesn’t really relate to anything else." In short: You do you.