Why are you doing this? What is your motivation? Do you think your friend will hold anything against you just because you don't do everything his girlfriend says? As for the girl herself, why does she insist on asking you to do all these things?
You really need to be assertive, she doesn't have much reason to stop these requests if you're always agreeing with them. Despite popular belief, you can still be a nice guy without doing everything for everyone else.
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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