If you offer to buy a friend something, but in the end you didn't want to cuz they (she and her friends) disturbed your sleep?
how do you say:
it's at my wish if I want to treat or not

Question

Answer

"It's up to me whether I want to treat you or not".
Though it comes across as a bit aggressive. An example would be if they asked you to buy them something even though you're mad at them, and you want to express that "it's not their decision to make".
Is that what you would like to go with?

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