What would u do if your best freind did this ??

Right well last week my best freind said something in front of the cl when were in the midst of a fallout. We were learning about healthcare roles in the NHS in Citezenship. The tutor said what is the role of a paremedic ? That is what my dad does. My freind turned away and said all they do is drive an ambulance ! looked back at me and smirked ! Anyway ever since then i really cant look at her the same and little things she sys i always pick up on its like i am seeing her in er True colors ?? What would u have done ? i know she did that out of spite. Thanks xxsamxx