Would it be wrong if your best friend after going out with the guy that you liked to start talking about you behind your back?

Well think about it a best Friend will never talk about you behind your back, will care for you in time of need, and will be there for a really long time, oh and you shouldn't have any doughs about your friendship in general so is this person really a bestfriend? I think not!So yeah If she/he did that is very wrong!