Needing to vent

My 5 year old step daughter and I got into an argument tonight over a sticker of Anna from the movie Frozen. Yesterday I found it on the floor in the kitchen with no sticky back to it and it was ripped so I threw it away thinking nothing of it. She normally leaves things like that all over the house and I clean up after her. Well she asked me where it was today and I told her I threw it away. Apparently that was the worst thing to say and she started crying and throwing a tantrum because of it. I guess it went to her school folder and I'm a liar because I supposedly knew that? I knew she put some stickers on her folder but it never once crossed my mind that that's what it went to. I assumed it was apart of one of her crafts she randomly does and leaves messes of. She proceeded to tell me that I am a liar and she hates me because I threw it away and she hates coming over to our house. I don't know what it is about being called a liar, but it boils my blood like no other!! I told her that there is a difference between being a liar and not knowing but she still called me one. 😡😡 She then demanded me to look online for a new Anna sticker.... No way am I going to spend money on a sticker especially after the way she acted over it! I went into her room to look for another sticker she could put in place of that one but none of them were good enough. I know this is something dumb to be venting about but it really got my blood boiling!! Oh the joys that come with parenting.