You can't get it wrong if it's the truth. You really like her, and that's nothing to be scared of, but you should also respect her current relationship, and make sure to maintain a happy/content lifestyle yourself. That's all you have to bother with, really; just be there for her like you always have, and if you want to let her know that you care about her, then be thoughtful about it. It IS close to Christmas, after all. ^_^