Question

Why so sad?

Remember we made an arrangement when you went away

Now you're making me mad
Remember, despite our estrangement,
I'm your man

You'll be back
Soon you'll see
You'll remember you belong to me
You'll be back
Time will tell​

Answer 1

I think the lyrics mean is a girl is jealous of the guy and when they split she still had feelings for him still while the guy forgot about her. so its basically about jealousy