Why couldn't the Creature, in Mary Shelley's Frankenstein, fully sympathize with the characters in Milton's book?

In chapter fifteen of Mary Shelley's novel
Frankenstein, the Creature gives his account (through Victor and
Walton--given this is a multiple narrative perspective) of his life. It is here where
the Creature details the reading of three novels: Paradise Lost,
Plutarch's Lives, and Sorrows of Werter.
According to the Creature, while all novels provided new knowledge, it was Milton's
Paradise Lost which proved most intriguing for him. The two
"characters" brought up in the novel are Adam and Satan. While the Creature can relate
to both, other aspects of each alienate him (the Creature) from them as
well.

First, he recognizes that Adam is unlike any other
creature on the face of the earth. In this sense, the Creature can relate to him. On the
other hand, Adam "had come forth from the hands of God a perfect creature, happy and
prosperous, guarded by the especial care of his Creator." Therefore, unlike Adam, the
Creature is not perfect, happy, prosperous, or guarded by his creator.

Second, he recognizes the fact that Satan has been exiled
by his creator. Envious of the love God had for those he embraced, both Satan and the
Creature fell short of the love of their creator. That said, the Creature was still
unlike Satan. According to the Creature, "Satan had his companions, fellow-devils, to
admire and encourage him; but I am solitary and abhorred." Therefore, unlike Satan, the
Creature had no one at all.