Should I be mad

 OK so the new semester has started And I return to my math class with my three other friends and we are all super close. Every time there’s a new quarter our teacher assigns us a new seating chart. so we walked into the room going to our assign seats for some odd reason my three friends are at a table together and I’m by myself with my teacher walked in and noticed that I was sitting alone and away from my three other friends he said “I didn’t realize you three were put to a table together and not Kyndal I feel bad I can move you guys together” I was pretty excited that he was thinking about moving me to the table with my friends and then one of my friends said “I don’t want her sitting with us because she’s a distraction and doesn’t know when to close her mouth I won’t get anything done if she’s at the table” and that bothered me so much and my teacher then decided that I was a distraction and decided that it wouldn’t be best to let me sit with them ..so for the rest of the day I sat at the table by myself while my three friends were at a table together I then talked to my two other friends and they apologize that they didn’t stand up for me and how it was so random they didn’t know how to respond. but they told me that what she said wasn’t right and that I should confront her about it and also they said they were going to vouch for me to go talk to my teacher and see if I can sit with them instead so I went to my teacher and apparently we persuaded him to allow me to sit with one of them at another table. so then I decided to go talk to my other friend who the one that who told the teacher I shouldn’t sit them (we are going to call her Amber) so I went to Amber to tell her how I felt, I told her how disrespectful she was and she made upset and that it wasn’t OK for her to talk to me like that and I didn’t appreciate it. so I expected an apology from Amber because I thought she noticed how upset I was but instead she giggled and said OK and that’s it I felt like after all that she should’ve just said I’m sorry and given a good explanation but the fact that she laughed at how angry I was made me realize that maybe she’s not a good friend she always feels like she has the right to say whatever she says and doesn’t expect anything back and I just now started realizing that so I decided that maybe it’s time for me to cut her off completely because it’s always me helping her and never getting anything back did I make the right decision.