To wear or not to wear

I want to start out by saying that I really enjoy weddings. Its the combination of love, family, friends, food, music, conversation and atmosphere that make it the perfect recipe for a good time. However, there is one problem that I always have...what in the hell am I going to wear? There are so many rules...black gives the depression impression, white is 'rude' to the bride, pants or capris are to casual and dont wear anything to loud that makes you the center of attention....the list goes on and on. I a m so worried about this because we have four weddings between June and September and I have no clue what I'm going to wear (I've actually bought and returned 3 dresses already). So I've decided to call out for reinforcements. I need your opinions and suggestions. Here's what I have found so far:

So there are a few of the millions I've looked at. You know, come to think of it, if people would just let me be in their wedding, then I wouldnt have to worry about what to wear! Is it rude to ask if I can be a bridesmaid??