Melina, I can sympathise with you but there's no need to be upset.

You'll find that the dud buyers are just a natural part of the business cycle and you'll see them come and go.

The best way to alleviate the stress is to have a system in place and I use a 2 step approach:

1. After 4 days have gone by I send a note politely explaining that payment has not arrived and eBay is now prompting me to open an unpaid item case against them. I also mention that this can impact their ability to purchase in future and ask them to respond within 24hrs.

2. Open the unpaid item case if no payment or reply is received OR cancel the sale at buyers request if I have eBay email verification.

If all sellers had their blocks in place it wouldn't take long for the habitual "grubs" to be weeded out.

PS - I had 2 from the weekend, both of whom paid up in response to the above. No stress involved.