What do I do?!?!?

My friend asked me to be a bridesmaid in her wedding in March. My husband and I are going through a very rough patch right now though and I don’t know if I can afford to buy the outfit she wants us in.... what do I do?!?

*added*

I know this really isn’t expensive for a bridesmaids outfit, but we are really struggling. I normally have a hard time just paying my phone bill and that’s only $45. She doesn’t have much money either so I’d feel bad asking her for money and I don’t have anyone to barrow money from.