Meaning of "now that the blood had gone out of them"

Question

‘Where have you been all day?’ said Philip. ‘I waited for you. Let’s go out and eat.’

‘I’m going on the train. Tonight.’

‘Wait another couple of days. We’ll fly back.’

She shook her head. The music stopped and the screen was filled with the smiling face of a young man.

‘Course,’ said the man, the boy, ‘an album’s a major statement of where a band’s at creatively.’

‘Aren’t you being a bit iron-clad?’ said Philip. He swung his feet to the floor. ‘It’s because I didn’t come back last night, isn’t it.’

‘Dexter came looking for me.’

‘Here?’ He laughed, and turned off the television. ‘Bloody Elizabeth. Big-mouth.’

‘I sent him away. He was crying.’

He bent his knees in front of the mirror and flicked his hair about. ‘I can’t help you with that one, Athena,’ he said. ‘Jealousy. You’ll have to handle that one on your own, I’m afraid.’

He straightened up and faced her. They were like two ghosts, now that the blood had gone out of them, two empty sets of garments hung opposite each other in a cupboard.

1. Is "now that the blood had gone out of them" an Idiom? or does it mean literally and it seems that the blood had gone out of them? I did not find such an idiom.

2. Does "Jealousy" in the dialogue "I can’t help you with that one, Athena. Jealousy. You’ll have to handle that one on your own, I’m afraid." mean "because of jealousy he cannot help her"?

Source: The Children's Bach by Helen Garner

Answer 1

My best guess for "Jealousy" is he is providing a reason for which he cannot help her, as you guessed.

As for "now that the blood had gone out of them", it is not an idiom. Here it is providing more description. Likely, it does not mean that they lost all their blood, but instead that they are pale, due to something like fear, in this case meaning that the blood has left their faces.