I agree, she's just too much of a slut to wear white, let alone a fucking wedding dress. The probability of her loving someone is low, but the probability of someone loving her would be even lower. This is not really because she's a succubus, but generally because she's a whore. She's hot and probably every man would want to fuck her, but no one would ever love a whore.
The white wedding dresses representing virginity grew along-side a Christian culture and didn't even come about until the 19th century, but now-days it's simply the "color of a wedding dress" and has as little to do with virginity and Christian purity as most modern weddings themselves. Especially seeing as she's a demoness and all that, I'm doubting she's having what one would call a traditionalist wedding anyways~~