Asked to be bridesmaid and go to hen do etc for friend, all fine. But the chief bridesmaid was recently bridesmaid for her other friend and as well as going to the hen do, her and the other hens did like an advent calendar-style countdown of gifts for the wedding (only 12 days, not 24!!). But these weren't little things like idk makeup or flowers, it was big gifts like handbags and a night in a nice hotel! 
She wants to do the same thing. Even with us all chipping in it's going to add up.
I can't afford it but also, happy though I am that my friend is getting married, and that she wants me as bridesmaid, I don't feel I should be obligated to buy her all these gifts just because she's decided to get married.
AIBU?
If not, how do I or can I get out of it?