Friend of 2 years getting married... Bridezilla!?

I have a friend who got engaged March 21, 2009. Since the very next day she has been planning her wedding. They've already booked everything from the ceremony/reception place, ordered the favors, etc etc etc. The list would be long believe me. She's been a pretty good friend of mine for 2 years now and we've always talked about when she got engaged how I'd be the planner (since I LOVE planning stuff & am good at it). Well her daughter decided to take over completely and even had her change her wedding color just because she wanted to use it when she got married later in life... (her daughter is 19). And the bad thing is she has totally let her daughter do this & I've been left out of the planning. She did ask me to come dress shopping with her yesterday, but was upset because we couldn't get there right when she wanted to because my fiance had a job interview and I was working. I already was taking off for her, driving 20 minutes out of my way in the complete opposite direction to pick her up and then driving an addition 25-30 minutes to pick her mother up and doubling back. The driving took foreverrrr and I barely got a thanks out of it. And she only tried on like 4 dresses because she was set on the first one she tried on (which is great, but she should have experienced a few more styles). Then today she is texting me while I'm at work every 3 seconds giving me another email address to send the pics of her trying on the dresses to someone else, or to call the honeymooon place for her since I'm "better" at it, or to do this or that... I'm freakin at work!!!! [[And to make things worse its my cousin's 22nd birthday... he passed away almost 3 years ago & we were close.. its a tough day for me). Anyway, she said I'm definetely helping her with the invitations but that for sake of no arguement I have to have her daughter approve everything. She's always been a bit of a user, but this time I feel totally taken advantage of. I've spoke up and told her how I feel and she blows it off. What should I do?