"No one can see the moon", the moon is where Chang 'e lives, and she is the only one, which means loneliness;
"Dark tears give birth to a secluded room" refers to a person secretly crying in a claustrophobic room;
Sad alone, and the artistic conception of the previous sentence, describe the inner sadness;
I don't know the exact meaning of "cloud lock bridal chamber", but intuitively it should be the yearning for love between men and women, but it can only be locked in the boudoir to create an illusion.
My answer may not be accurate, for your reference only. I hope I can help you!