Hi roshrang,
I agree that if you’re not fairly certain she’d say yes, then you should WAIT.
But reading between the lines, it seems like you have a lovely relationship where more things are left unsaid than said, and therein is where the magic lies.
I would drop a few major and minor hints this year so she can gracefully tell you “no” in so many words (or “YES”!) if you know what I mean.
Like, “Do you want to be asked an important question before or after the holidays?” If she smiles, blushes, and acts coy and purrs, “What KIND of a question??” your answer is YES.
But if she grows flustered and stammers while looking for the nearest exit the answer is NO.
A simple, “So, what’s your ring size?” could do it.
Good Luck!
Inky