"I then told her it would be best if we cancelled the sale"

Did she agree to the cancellation, if so by all means follow up with eBay.

However if she didn't reply or said no, I would be very cautious about speaking to eBay, cancelling sales is a major NO NO unless its at the buyers request or there is an issue with the address. Do it for other reasons can get you a policy violation. A few of those will see your selling on eBay ended. I would be checking the address very carefully and if there is even the slightest issue with it use that as the reason for cancelling if asked.