What you need to do is have you and your friend make a plan to spend time together, just you and him. If his girlfriend is understanding, she'll allow your friend some personal time without her.
If not then, well I'm not sure what's the best way to tell your friend that their girlfriend is being selfish(among other things), but I think it needs to be said.
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Congratulations, LMS. In a topic where Liquid Wind said that women shouldn't be allowed to vote, you are still the worst poster in this topic. - kevwaffles