Although I don't practice in Oregon and Oregon laws may differ, there are certain truths about Intellectual properties and defamation claims that hold true across state lines. When it comes to suing someone for slander, usually as long as the statement was a FALSE statement and it was communicated to a 3rd party and you suffered some harm, then you can definitely sue. Just remember there can be no TRUTH to the statement made in order to prevail.
As for the claim regarding use of your picture, based on the information you gave, the use of the picture doesn't really factor into the lawsuit. You might have a claim for misappropriation of property, but it's a stretch.