I don't think it's a bad idea withdrawing or exchanging some Bitcoin to fiat and spend it on Christmas stuffs if there isn't any alternative source of income, this is yelutide season which is synonymous with giving out some gifts to our love ones, to the poor and gifting Christmas hampers etc. Christmas it's only celebrated once in year it's a joyous occasion celebrated globally, thus this is not about throwing some Bitcoin away, but taking out some bit for personal enjoyment and merriment after working throughout the year, Merry Christmas 🌲 in advance to forum members.
Christmas is a special celebration and I also do not think that it is bad to have a budget of some bitcoins that you would sell off to make the occasion memorable both for you and your family. The thing is just try as much as possible to keep your spending moderate and don't overdo or over sell out some coins to finance your celebration. Christmas did not come suddenly so it definitely means that you must have been making financial plans for a while about that day to avoid or reduce the pressure of needing money to spend.