Q:

Meaning of sentence in Frankenstein

In Frankenstein, Chapter 15

I cherished hope, it is true, but it vanished when I beheld my person reflected in water or my shadow in the moonshine, even as that frail
  image and that inconstant shade.

Monster's hope vanished when it saw its horrible image.
But what does ", even as that frail image and that inconstant shade."  indicate here?
Does the "even as" and "that" in this sentence serve for?

A:

Examining the sentence, which says "I beheld my person", it mentions two ways in which the speaker does that:

a) reflected in water
b) shadow in the moonshine

The two phrases further on in the sentence, about which you ask, refer to those two images, respectively:

a) that frail image (reflected in water)
b) that inconstant shade (the shadow)

What "even as" does, is to say that the speaker's appearance was horrible, even when seen indirectly in those ways.
So to paraphrase the sentence:

I hoped that I did not look awful, but even mere suggestions of my appearance were enough to destroy that hope.

