The holidays are filled with opportunities for us to be intentional about guarding our peace as well as to give generously when we are able.
The trick is to give from your "best yes." That means giving intentionally, out of love, and because you want to. It also means knowing when to draw the line at giving of your time and resources when you only feel obligated (which isn't a good way to love people because you end up bringing resentment into the relationship).
If you need to brush up on your boundary skills, here are two of my favorite books.