You know what's going to bother you this year, because it's likely the same thing that bothered you last year, and the year before that. You can't stop your sister in law from making a comment about your single status, but you can say that you're enjoying being on your own and haven't had this much fun in years.
Your outlook is a product of your own relationship with expectation. What will or won't happen, no one knows. And how we deal with the stress of not knowing, whether to hope for the best or expect the worst, the idea that our expectations always directly affect an outcome is little more than magical thinking.