This quote from Karin Slaughter's Pretty Girls paints a vivid and relatable picture of the complex relationship between parents and their teenage children. The comparison of a teenager to a 'really, really shitty roommate' humorously captures the everyday challenges parents often face—songs of frustration about inconsiderate behaviors like sneaking food, borrowing clothes, or taking money. These common grievances resonate with anyone who has navigated the turbulent years of adolescence alongside a child.

Yet, this candid portrayal takes a poignant turn as Lydia acknowledges the unexpected emotional transformation that comes with parenting teens. The idea that teenagers ‘soften you’ and ‘smooth out your hard lines’ suggests that despite the friction and occasional exasperation, they bring out growth and softness in their parents. It reflects a powerful dynamic where both parties evolve; the teenager may test boundaries, but they also awaken empathy, patience, and a deeper sense of self-awareness in the parent.

What strikes me most is the notion of becoming 'a better version of yourself that you never even knew was there.' It hints at the transformative power of relationships—the way love and challenge intertwine to foster personal development. This transformation is subtle and sneaky, not recognized until much later, much like the teen themselves growing into adulthood. Overall, this quote balances humor with warmth and truth, standing as a tribute to the messy, challenging, but ultimately enriching experience of parenting.