See, that kind of thinking will get you in trouble. If you KNOW that an action will hurt the band, and you do it anyway, then YOU are at fault.
What you ned to do is have a band meeting and set some rules and responsibilities. Nothing is easy when more than one person is at the wheel. Remember learning to drive with your Dad? Same deal here - giving advice needs some serious "splenda" coating (Atkins, you know) and you should expect some dissention within the ranks.

You need to determine if this band is a co-op or something else. If it's co-op, then you need to assign responsibilities to each member. Booking, advertising, ehancements etc.... everyone has to do their part or it will self destruct from within.

This is why so many of us work solo routines now. It's not all about the bread. It's the ego trips that break up bands.