How can I possibly publish my poetry, on my website, without it being stolen? Is this, completely possible? I mean, I guess I would have to get a CC license. But, this most likely wouldn't stop people from stealing it. All suggestions appreciated...

Not possible. A copyright of any sort will help you defend any infractions in court, but there is nothing you can do to stop a person from stealing text. There are things you can do to make it harder, but not stop it.

Require the users to return a url to your website, people hate advertising sometimes! lol