I always thought Alessa's feelings towards Dahlia were fear rather than love. That's why she couldn't hurt her (until the very end, but that because she believed that god would punish her) and Dahlia forced her to use her powers to kill people, like Gucci, who were too close to finding out the truth about the cult (that they were the ones who run the drug rings) and that couldn't be bribed (and because it seems the police never seems to take serious action, it's implied that they've bribed a whole lot of em').Perhaps Dahlia pressured her daughter into doing it? It seems that Alessa was very keen to get affection from Dahlia; she really seemed to love her at first. Even when Silent Hill is pulled into the Otherworld, Alessa doesn't kill Dahlia (not until the end), even though she has the power to do so.
It seems that Alessa might have killed Police Officer Gucci (among others) if she thought it would make Dahlia love her.
Anyhow, I doubt that's Gucci in the bathroom stall as he had died quite a while before it all went straight to hell.