Against my wishes, my mother bought a white dress to wear to my summer wedding. She is doing a lot to help with planning and I don't want to appear ungrateful, but I wish she wouldn't wear it. Isn't that sort of tacky -- wearing white to a wedding? I don't know what to say to her, and she's quite good at shooting me down. I do understand that this is a big day for her, too.
Well, technically no one but the bride should wear white to a wedding. But the reasoning behind that "rule" is that a woman who wears white to another woman's wedding is trying to upstage her. In your case, it sounds like it's highly unlikely that your mom is doing that. As long as her dress isn't lacy and frilly -- meaning, as long as it doesn't resemble your dress -- it's okay for her to wear it.
Of course, it's okay to make your feelings known, too. You don't have to get into an argument -- just say something like, "Mom, you know how much I appreciate all the help you've given me with wedding planning, and I know my wedding will be a big day for you, too. But I'm a little uncomfortable with the idea of you wearing white." This may or may not change her mind, and she might get defensive, but you have a right to say it. If she tries to draw you into an argument, just refuse -- say, "Look, I just wanted to tell you how I feel, that's all." In the end, don't worry too much about this. Either way, you will be the center of attention on your big day, and your mom will be glowing, too.
See More: Bridal Party Fashion , Family & Parents , Basics for Moms