my friends expensive wedding 😔

I was asked to be a bridesmaid in my best friends wedding, so of course i said yes. but i didn't know it was going to be so expensive and i have 2 kids and only work part time. and my husband doesn't make much more than me. it's 4 hours away and we have to pay $300 for a cabin, $200 for a dress, at least $100 for bachelorette party plus her gifts. plus gas abd food and drinks for cabin and whatever we do the night of the party. I'm stressing out about it and i have until November, but I'd have to save every single check to buy all this. I'm starting to think I should back out and just be there the day of instead of be in it but idk 😔 she was in my wedding but her dress was only $60 and it was 30 minutes away.