How do I get rid of my girlfriend's friend Whose always there? ?

She's always there I Live abet far from my girlfriend so I only get to see at the weekends and her friend is always there is am dating her to which is like what the hell I do get along with her and she's a good ish but she does not her that couples need time alone so they can bond i just don't know what to do I don't want start up something that could up really bad. Me and my girl have been going put for 9 months now and in love but I think am reaching my limit to how much annoyes I can take from her friend.