This is a member to member Board.
First contact your seller and explain your discontent. Attach pictures if you can.
The seller may tell you to return the item for a full refund or may charge a restocking fee. When you return the item use a service that gives you Confirmation of Delivery. (Most parcel services to Canada and the USA do this automatically.)
You can leave feedback and so can she.
If the seller does not want to take a return, go here:
http://resolutioncenter.ebay.ca/
The first instruction will be to contact the seller. You will already have done that.
You will be told to return the item to the seller with Confirmation of Delivery/tracking.
If the seller does not refund you herself on receipt of the returned purse, Paypal will and go after her for their money. There will be other fallout for her. You will not be allowed to leave feedback.
Don't spend too much time with the seller. You have only 30 days from the date of delivery to file a Claim.
However.
An item that has been on display in a shop may show signs of wear, but still be technically "New with Tags". The seller should have described any such faults in the description.