Late Ideas

I feel like it's a bit late for more ideas, but I'll post this anyway in case it's some how used.
The bus I catch in to town for course is pretty early, like the sun is rising and I thought of the colours in comparison to the colours we'll be using in our scene.
The husband - blue = cold
The wife - orange/yellow = warm
With the sunrise, the sun meets the sky. We can think of Elizabeth being like the sun. She is the warmth in the husbands world, as if he's the sky.

BUILDING ON THISSSS
Then we bring the sun and moon into the picture.
Taylor suggested a painting of a sunrise in the scene.
I can take a photo of a sunrise and put it into photoshop to fit in with the scene.
There are 2 sources of orange light coming into the apartment being the streetlight outside and the orange aura light coming from the mirror. The shot where Elizabeth fades away, the orange light form the mirror world would fade also, leaving only the streetlight light the only source of orange light.
As Elizabeth is fading, the shot can change to focusing on the sunrise photo. The orange light from the mirror will be on the photo and the orange light will fade on the  photo, becoming more blue.

ALSO as Elizabeth fades, the streetlight can flicker and go out. This will bring the moonlight into the apartment, so the apartment will mainly, if not entirely be blue. Then the sunrise photo could be seen as a sunset.
The moon would represent the husband and the moonlight would shine in as if saying that it is ok to be alone.

The moonlight can shine on the husbands face when he is looking at the polaroid photo on the mirror. This lighting will be a lot more soothing than the streetlight.

Just to get one thing straight, he isn't really the moon, and she isn't really the sun, if this was the case then they'd never be together. 

References

http://e2ua.com/group/moon-wallpapers/

https://springwolf.net/2014/06/09/the-legend-of-the-sun-and-the-moon/

http://7-themes.com/6982647-sunset-over-sea.html