My question involves a roommate in the State of: New York
I'll cut right to the chase. My ex roommate, who used to be my best friend, decided to move out. She's been nothing but a horror the entire time. She still has some of her things here, she has some of my belongings that she said she would return, the house keys, and still has not paid her half of the last month's electric bill. I have contacted her dozens of times for her to get her things and return mine, and the few times she does respond (when she feels like it) she says she'll come but never does. It's been over a month now. She's quite spiteful, too. When she left, she left her trash, including stuffing a small room in the back with a mountain of trash bags (never bothered to tell me) and it was just discovered the other day that she had left last Halloween's pumpkin in the tank of my toilet. I have tried so hard not to stoop to her level and to work with her, but I've gotten no results. Now, I want to consider taking legal action, but I don't know what my options are.
Her name was also on the lease, which is somewhere in the mess of my house. My landlord lost her copy, but may be able to get another or at least state that yes, she lived here. I may have some mail of hers here, I know I have her boyfriend's mail. With the electric bill, only my name is on it, but obviously, since she lived here, she was using it. I still have that bill, the picture of the toilet pumpkin on my phone, and emails to her.
Do I have a case against her? What are my options?? I mostly just want to threaten her with the prospect of taking legal action and to point out that I can (if I can), but if need be I think I would take her to court since I am so sick of taking her crap.

