real question how come she eidnt call the police before she went in

She most likely wanna handle them herself cause she had plenty of reasons to call the police and she could have even had Patricia ex friend tell the police everything since I believe she was the one that saw patricia “kill” Peggy. But Peggy probably wants to take her revenge the harder way and deal with patricia herself instead of just doing the easy way with calling the cops. But with the guy it would be harder to call the cops since he is a stalker killer that would kill both if she would have called the cops. And it would be harder for her to save Chester if she did.