Shouldn't "Jeg ser dere." work?
Why is 'Jeg ser du' not working?
Du is the nominative form, deg is the accusative. Similar to how 'i see he' is wrong.
I loved Avatar
...said the Norwegian Sauron
What is the subjective and objective forms of 'you'?
du = singular subject
deg = singular object
dere = plural subject + object
Is "deg" used when specifical directing a sentence towards someone then? ie I see you or it was you?
'Jeg ser du' should work too. Or you should specify if singular or plural.
No. "Du" is a subject pronoun, and "you" is the object of this sentence.