You don't have to wear white.
Until Queen Victoria was married in a confection of white lace and silk, it was traditional for the bride to wear either the best dress she already owned (Often the dress she wore at her Debutante ball) or to choose a gown that would thereafter be her "Best Dress"...at least until fashions changed.
And this business about white signifying virginity is just plain vulgar....it IS traditional that white should only be worn by a young lady marrying for the first time, but the colour of the dress makes no statement about the body wearing the dress....more experienced brides, remarrying after being divorced or widowed, are often given funny looks if they wear white, so most choose not to defy that convention.