Opinions please

Brianna • TTC my Rainbow Baby ! Miscarriage 12/26/14 & Ectopic with Left tube removed 5/20/18😇😇
My friends sister asked me to be her kids godmother I'm not close with her at all but I have known her and her family over 10yrs so I agreed .. The kids first bday party was getting planned I agreed to help pay off the club where she was hosting .. 500$ in total I gave up.. Come to find out the bday party isn't happening ..&I Never was offered my $ back .. I actually work for my $ and this girl makes 15$ an hour being her mother's home maker when she hasn't even been to her mother's house all summer to help her do anything but is still receiving her checks .. 500 is a lot of money that I could have used for cable, cell bills, rent etc .. Should I ask for it back or just let it be and say to put it towards what the kid needs ?