HOLY FUCKING SHIT. YES.
Yes yes Y E S.
Nah, pretty sure Loki knows, and that’s why when Thor makes any slight toward Loki, it’s that much more of a betrayal to him.
Loki said all he wanted to be was his brother’s equal. Thor, however, made it a point to prove himself (rather unnecessarily) to everyone around him, an arrogance which Odin only fueled by requesting warriors to fall to him in sparring matches (comics/Tales of Asgard). Meanwhile, no one pays mind to Loki save for Thor who only rants to him about whatever slights are done to himself, instead of hearing Loki out when he has any troubles he wishes to discuss. That small slight, happening over and over, makes Loki understandably feel ignored by the one person who appears to love him at all. His reaction is so strong, because when Thor begins to ascend the throne, he begins to resemble Odin. Loki is certainly not Odin’s favourite and Loki reacts strongly in order to prevent Thor from becoming their father.
Yeah….at least, within the movie-verse mythology that makes sense, I think.