I've never had a problem with La Garconne. I find the level of anger about not taking a return surprising, ladies. La Garconne is a very good site that is not trying to scam anyone; AG bought these shoes at end of season at extreme markdown and LAG is very clear about things being final sale. So it's not out of line that they really are, as LaG says, final sale.
AG, try contacting the designer like Rae suggested, maybe you'll get them repaired. But the fact is, sometimes things are final sale and that's life. AG took a chance, it didn't pan out, she doesn't get a return... She tripped in the shoes and they ripped. It sucks but it's not La Garconne's fault.