Stand up to friend's GF?

I have a friend who's with his girlfriend right now. I know this because he was talking on his cell and said "sorry, not tonight, i'm hanging out with abbey." If I were to call right now, I guarantee she would answer his phone and say "What did I say about calling James when we're together (or on the weekend, if it's Fri/Sat.)? And then get very angry. First of all, he pays for his phone, so it's not hers to answer. second, I have just as much right to talk to him as Abbey does. Third, our conversations would consist of "i was wondering if you wanted to hang out tonight, but since you're with her that kinda shot my plans down, but wanna do something later?" 45 second phone conversation. it takes her longer to answer and get angry than it does for me to talk to James. In a nutshell, I can't stand this b!+ch and hope that he kicks her as$ to the curb and finds a better girl (which wouldn't be hard) The next time I call and she gives me her attitude, should I give i stand up to her? I talked to James about it and he said he's cool w/ me standing up to her, and frankly I don't care if she hates me. what do you think?