I need ur help URGENTLY?

I have 3 best frnds- shr, sam, and nav. Me n shr had joined a camp for a month in our vacations. On the last day shr comentd on nav. On the same day i taunted nav for having a bestest best frnd shr (i was jokng bt she took it seriously) we did talk to each other after that bt nt like before. She says i have changed n dat i am nt interestd in talkng to her. Do u think it was my fault n i should apologise? or smethng else. Please help!