As you plan your wedding day, ensure communication is first- Ensure that you try to limit the stress- If any1 in the bridal party seems to not be able to commit - keep it simple. First, Have a discussion and ask them to simply be a guest if they cannot commit financially-
Your wedding day is not their day and they should not go broke for the bride and groom - however it is still YOUR day & it should not have to be changed because of the people who are involved- Don't feel bad and don't be sorry- DO things your way!