"Overly friendly" could come off as "insincere" or "pushy". If she is not picking up that this behavior does not have good results, or if she can't tell that she is making people uncomfortable, she may need more explicit instruction in how to read social cues and body language. Role playing or play-acting where the two of you take turns showing different emotions in response to different situations, especially without using words, can be helpful to teach kids who don't necessarily have an automatic grasp of these things how to read people's non-verbal signals.
