Personally, I think that Maria's soul has disappeared into the abyss and the main character's soul is in Maria's body to stay. So, when the main character dreamt about Maria, it was probably just a manifestation of her guilt, fears, and doubts. And at the end, the main character's thoughts when she regains consciousness are probably symbolic of how she's thrown her old self (her old life) away in order to embrace her new one with a fresh and clean slate.
Personally, I think that Maria's soul has disappeared into the abyss and the main character's soul is in Maria's body to stay. So, when the main character dreamt about Maria, it was probably just a manifestation of her guilt, fears, and doubts. And at the end, the main character's thoughts when she regains consciousness are probably symbolic of how she's thrown her old self (her old life) away in order to embrace her new one with a fresh and clean slate.