Mad at an Old Lady

Every now and again, I get pissed at an old person. I rarely yell at them because I know that many of them do not know what is going on today. Last night, I was especially angry at one person in particular. I was almost willing to get a battery charge for hitting an elderly woman.
Zack's grandparents are two-faced liars. Phyllis was telling me that she would write a check. Things went south when I was obligated to call the law when something illegal was going on. His grandparents have come to the conclusion that Paul and I are causing trouble. Well, no, I'm protecting myself and my home.
Zack has chosen to leave. I didn't kick him out. Paul gave him a 30 day notice, despite him not paying rent. By law, it is supposed to be three. He came back last night to get more things with his grandparents. I watched them so I would not have anymore things vanish mysteriously or get damaged.
By the time they were getting ready to leave, Paul wants to talk to Zack. We had calculated a back dated amount plus late fees. Paul tells Zack that he was not trying to cause him trouble. Zack says, but he did. His grandmother butts right in and acts like she has authority over the situation.
Paul gives him the reason why Zack cannot be breaking the law in my home. He has a daughter that he will not be able to see with the crap going on in my home. His grandmother starts to put her two cents in and Zack began to argue. They proceed to tell us that we could have told the kids to leave and that Zack didn't buy the beer. How the hell did the kids get the beer?
At this point I start to tell her that I made the rules and quite frankly, it is illegal and he still had them there. She grabbed the invoice that I made. She snottily said over and over, "He did not sign any lease and there are no late fees. I pro-rated it already."
Then she kept on saying that it is illegal to kick someone out. I told her that there is no law about the winter and that Zack chose to leave. I already went through this with someone else. She quipped, "Well, you probably got away with it." Her husband started to chime in telling me to talk to an attorney and it is a matter of an attorney. She took the invoice and tore it in half.
I looked at her coolly, "Get out of my house." They continued to escalate and acted like they had a right to stay there. Phyllis went on and on how it is illegal to kick him out and objected to the three day rule law. Her husband started to yell at me, I pointed right at him, "I told you to leave. You are not welcome here."
They finally left. I called dispatch that they are not welcome on my property. I was told to call back if they come back again. I am so livid by now. I looked and looked. Minnesota has a law about evicting during the winter. There is no law in Idaho. There is for someone who is 16 years old.
The only law I found was that it was illegal to shut off utilities during the winter months. Why do people try to talk smack when they are clearly wrong? It is so stupid when someone says that they are going to call a lawyer. Does that really cause a concern? No, it does not because I know what the law is and if they fight me I will win. I have messages. I am willing to take a sample from the backyard. I can take pictures of damages that he has done. I will even take the paperwork that she tore up. Give me a break.
Then she had the nerve to call me this morning while I was working on school. I am infuriated at her. She was asking for my last name. No apologies for acting irratically. I really did not want to give her any information or speak to her and that she cannot. She proceeded to tell me that she wanted to come get his things and get it over with. I am so upset with her, I could not respond to her anymore. I just hung up the phone. I'm still upset, I can't understand anything that she was trying to tell me.