If the dress you bought looks nothing like what you ordered get a CHARGEBACK with your creditcard.
It is a bit of hassle, you need to provide printed emails with all your complaints to herdress and their responses and then possibly send them links to review sites to bolster your case.
Trustpilot is another site with plenty of disgruntled herdress customers.
Tip for consumers: Apply for a chargeback with your creditcard