Wham!’s “Last Christmas” is one of the top-selling Christmas songs, and originally written and composed by George Michael. The video of Wham!’s Last Christmas came out in 1984.
Let’s take a closer look at the lyrics:

Last Christmas
I gave you my heart
But the very next day you gave it away.
This year
To save me from tears
I’ll give it to someone special.

Last Christmas, the man gave the girl (someone special) his heart, but the next day, she gave it away.

In the video, the man (who George Michael plays) was giving the girl (who Kathy Hill plays) his heart (the gift of “brooch”) last Christmas in front of the fireplace.

George Michael in Last Christmas

A year later, this Christmas, he is longingly staring at the “brooch” that her new man (who Andrew Ridgeley plays) is wearing, which indicates that she gave the “brooch” away.

Andrew Ridgeley and Kathy Hill in Last Christmas

The man is still in love with his ex, even if he is with his new girlfriend this Christmas. Take a look at the lyrics of the “Last Christmas Pudding Mix”:

I’ve got you here to stay
I can love you for a day

It sounds like the man wants her to stay, so that he can still love her for a day.

George Michael seems to be a hopeless romantic guy, which is why his songs, melodies and lyrics have caught millions of people’s hearts. We all fall in love sometimes, and we get hurt sometime. Some people move on right away, but some move on in a couple of months, and it might take a year for some people to get over a broken heart.