This passage is from The Children's Bach by Helen Garner
Dexter emptied his bowl for the last time, then lifted it in both hands and licked it out, pushing his face right into it. There was soup on his nose, his chin and the front of his hair. He wiped it off on the sleeve of his jumper and sat back with a sigh. He was fed: now he could be sociable again. Nothing, thought Vicki, could be worse than the way he eats. Now things can only get better.
The soup was thick. The bread was fresh. The stove’s dry heat reddened their cheeks. The walls curved in around them. Outside the house, which was at the bottom of a neglected street, no cars passed.
Not late, but in a starry cold that lifted them off their feet, they went out to the car.
Does "Now things can only get better." mean:
Only from now on his behavior will become better?
Only from now on Vicki will feel better sitting there in their home?
Is Vicki thinking that now things can only get better?
Is "starry cold" used metaphorically, meaning: very cold?