It's probably not too white for most brides (and wouldn't have bothered me at my wedding).
That being said, I would avoid any and all majority white dresses as a guest, the risk of upsetting a bride (one you presumably like enough to go to her wedding) on her wedding day isn't worth it. Therefore, I say find something else OP.
I always disagree with comments on colour shoes pashmina/jacket, shoes, bag.. If you get warm then the cover up comes off. While sat down your shoes and bag will not be visible. So these don't make much difference in reality.