You should not tell your partner who to communicate with.
Gerry is dating Allana, and Gerry finds Allana's friend Lucy very annoying.
Gerry wants to avoid Lucy.
Gerry tries to be away from home when Lucy is around.
Gerry tells Allana that Lucy is annoying and that she can't talk with her anymore.
Lucy notices Gerry avoids Lucy and tries to set things up so that they meet when Gerry isn't around.
Allana tells Gerry to go somewhere unpleasant and breaks up with him on the spot.