Just Titanium Rip off quality of product - no refund or exchange policy on faulty goods! New York, New York

I purchased a men's diamond ring in Feb 2012. In April 2012 the diamond had fallen out. At the time I was asked to at my expense to send the product back to get it fixed. On 16th April 2012 I was assured that the diamond would be securely fixed and that I wouldn't have issues with this ring again.
Now in Nov 2012, the ring has fallen out again! On both occasions I emailed Jennifer at sales@justtitanium.com. The ring has a manufacturing fault and cannot hold a diamond successfully. This product was not cheap to purchase! They are willing for me to keep paying more money at my expense to have it fixed even though the fault lies with your product. I feel the purchase agreement between seller and buyer has been breached as all they have offered is limited options all at my expense with a shabby product not fulfilling what it has advertised.
I offered a compromise whereby you exchange the product without the diamond and refund me for the diamond that is causing the distress. However, they have declined this. WHY?
I think they'd wish I'd just accept paying for an expensive item which lacks advertised quality and disappear at your gain? I am dissatisfied by the way my case has been handled. 

I would stay well clear of this company. It is based in US but it is manufactured in Hong Kong.... Quality and customer care is the least of their worries. I'd be very wary even entertaining the idea of buying here.