Whats the best way to ignore my mom for a few days?

look i love my mom but shes such a hypocrite and so fake. Like for example she says she hates it when people talk about other people behind there back but right now shes in the kitchen talking to my brother on the phone about a bunch of people at work. And i swear with my brother she wants to act like such a strict parent and such a smart and bossy person, she likes to talk about me to my brother in a bad way but whenever he leaves she is a TOTALLY different person. She would walk into my room give me a hug and smile and ask me to hang out with her and think that everything is ok. I want to show her that she cant just change back and forth with me like that, that i want only one mother. So I want to ignore her for the time being and show her that Im seriously upset with her this time. Im 14 by the way and yes you might think oh its just some teenager in a fight with her mom but its not like that at all. Im also not looking for insulting comments or anything Im being really serious. Thanks :)