Well, I'm not Catholic -- but neither am I blind to how the early Church understood the Eucharistic meal as the actual body and blood of Christ. So if I am deluding myself, I'm in good company.
Within the first two centuries after Calvary, we find the testimony of Ignatius, Letter to the Smyrnians ch. 7 (“They abstain from the Eucharist and from prayer, because they confess not the Eucharist to be the flesh of our Savior Jesus Christ. . .”); Justin Martyr, First Apology, ch. 66 (“For not as common bread and common drink do we receive these; but in like manner as Jesus Christ our Saviour, having been made flesh by the Word of God, had both flesh and blood for our salvation, so likewise have we been taught that the food which is blessed by the prayer of His word, and from which our blood and flesh by transmutation are nourished, is the flesh and blood of that Jesus who was made flesh”); Irenaeus, Against Heresies, Book IV, ch. 18 § 5 (“Then, again, how can they say that the flesh, which is nourished with the body of the Lord and with His blood, goes to corruption and does not partake of life? . . . For as the bread, which is produced from the earth, is no longer common bread, but the Eucharist, consisting of two realities, earthly and heavenly; so also our bodies, when they receive the Eucharist, are no longer corruptible, having the hope of resurrection to eternity”); Irenaeus, Against Heresies, Book V, ch. 2 § 3 (“When, therefore, the mingled cup and the manufactured bread receives the Word of God, and the Eucharist of the blood and the body of Christ is made, from which things the substance of our flesh is increased and supported, how can they affirm that the flesh is incapable of receiving the gift of God, which is life eternal, which [flesh] is nourished from the body and blood of the Lord, and is a member of Him?”).
Such was the currency of the doctrine two centuries before Chalcedon, a millennium before Aquinas. I am not prepared to be dismissive of this history.