(of a person) with thoughts far away from her or his surroundings or work

illusory, romantic

(appearing) tired, unenthusiastic

careless, indifferent

giving no thought or care to something; not having or not requiring intelligence; not having a purpose

oblivious, stupid; automatic

a state of mind in which something takes up all a person's thoughts

absorption

so deep in thought, so carried away by feelings, that one is unaware of other things

absorbed, fascinated

careless; negligent

careless, thoughtless

not aware

ignorant

(especially) not having, made without, adequate information

unaware

existing only in the imagination and unlikely to happen; (of a person) having grand (and often impossible)

idealized, romantic

having, expressing, a wish

desirous