Willow Rosenberg’s transformation from a shy, geeky girl to a dark, angry wicca was present right from the beginning of season one. Throughout the seasons, she is often painted as insecure and easily bullied around by her peers. However, when she begins to use magic, Willow is authoritative and demanding of her peers. Her desire to have this constant control keeps building up (her attempt in Something Blue to get whatever she wants, Willow stealing a dark magic book in Tough Love, etc.) until Willow becomes addicted to magic to live her life.
Willow: There’s a simple answer to this. Just think about who loves him the most. Clearly I do, since I’m willing to look past the whole orientation thing! Anya: Well, you’re gonna have to do better than that!