Time to think about who you choose is usually not necessary. Even if you and your loved ones with only a week and a girlfriend you know all my life, from a friend's need to get rid of. This can be done in different ways. It is best to just say a friend in his eyes everything that you think about it. Even if it begins to make excuses and try to convince you that you have misunderstood the meaning of her actions clearly let her know that one of you and your loved ones you do not want to see her. If this option is not right for you because of its straightforwardness, can use avoidance tactics - not to call her friend herself, and if she calls, break off talks at the first convenient excuse to avoid joint outputs anywhere with it and with your loved ones, and so forth.
However, a more complex situation, when your girlfriend says that the man you absolutely not fit, and trying to embroil you "the best of intentions." In this situation, you may be very difficult to break up with her at all, because it does so because of his love for you. Exit here one - to sit down and talk to her on the souls. Tell her that you understand why she does, and so do not want to lose her. But if it continues to behave and on, you stop talking to her.
In that case, if you decide to try to keep the relationship with his girlfriend, tell your loved one about their suspicions. Let it be on the lookout, and if she will be accepted for the old, does not give in to provocations. And a friend will not be able to continue in the same vein, when the two men whom she tries to embroil know about her intentions.