There are several at the end of the book in Chapter XXIV when Victor is nearly finished telling his tale:
"My life, as it passed thus, was indeed hateful to me, and it was during sleep alone that I could taste joy."
He goes on directly after this to explain that in his dreams he is able, once again, to hold his friends and family (specifically he names Elizabeth and Clerval). He misses them terribly and the very act of being awake is tortuous for him because he knows they are dead.
"All my speculations and hopes areas nothing; and, like the archangel who aspired to omnipotence, I am chained in an eternal hell."
He has no hope if he lives and he has no hope if he dies. His destiny is sealed and promises nothing but misery.
"Oh! My friend, if you had known me as I once was, you would not recognize me in this state of degradation. Despondency rarely visited my heart; a high destiny seemed to bear me on, until I fell, never, never again to rise."
Here he is acknowledging that he was fueled by his ambition and belief in his own great destiny and he also seems to acknowledge that his fall took him a bit by surprise. It is a fall he cannot recover from.