Hi,
She might at least have called to explain. There's gratitude for you.
What does the latter mean here?
There's gratitude for you. The purpose of this remark is to draw the listener's attention to the situation. In addition, the speaker is using sarcasm. He really wants to draw the listener's attention to the person's ingratitude.
Consider this more concrete example.
I look out of my window in July and am shorrified to see a metre of snow.
I point to it and say to my wife, 'Come and look. There's a great Canadian summer day for you!'
Best wishes, Clive