Is a black and white dress appropriate to wear to a wedding?

I was invited to my boyfriends brothers wedding where my boyfriend is the best man, aka i have to meet his entire family and don't want to look bad. He told me to wear a black dress to match his tux, but i read you shouldn't wear a black dress or a white dress to a wedding and the dress i have is black with a white bow and stripe, do you think it's still appropriate? Or should i wear something completely different?