The thing is, that the intentionality has developed since antiquity, and was part and parcel of Platonism, held in by by Aristetolian logic, which started to upend it.
It was coined from the Latin, ‘intendere’ and held in a reverential modality, having affinity to scholasticism, with religious overtones.
Dualism reached a crisis of confidence with Descartes, who reaffirmed the rational part of it, through sustaining causal relationship with the Church and God.
Another crisis, the coming with the monarchical vested values, (corresponding with Your conflicting values) where the world coming out of feudalism, entered the age of discovery.
Husserl/Heidegger returned the idea of transcendence, transcending the modus operans of the cogito, with that of perception.
Without going through all the gyrations /contraptions that intellectual formations went through, through innumerable volumes, it is possible to extract essential movements , even of those most intricately and it times contradictorily befitting ideas in the obtruce manner that signified their writings.
So here ill try to describe the manner in which it went, albeit with a very wide latitude.
The intention signified a subject drawing a line , to move forward toward an object, both of material and mind.
Such was the historical effort to minimise or even negate duality. Some of the objections were stopped by God, whose function and role as a causal agent would have been interpreted as a sin by the holy see.
By the time Husserl got hold of the idea, god, as he was interpreted previously, had become almost passe in philosophical circles, so they had to come up with a different interpretation, that of intentionality and Dasein.
How that worked was kind of like getting through the backdoor, with a subliminal idea based on contingent logic.
In the very beginning, the idea of thingness, part and parcel of consciousness, began a unified field consisting of both: the subject and the object. It was an anamolie which began the very long quest into the reinvention of intentionality, while contemporeously affirming the primacy of singular Preception.
This is needed after all, to assert that, after all, we are singular entities. However assigning some thing as elementary as substance, could no afford to differentiate from I
conscious counterpart, thereby foreshadowing the Collusive or suppressive nature of substance within its own idea of it.
This is akin to what Bertrand Russell has been charged with the fallaciousness of his idea of sense data.
I hope not to involve You or presume on You that this historical anecdote is somewhat unfunctiobary, but it did, a while ago help me fill in the dots.
As it goes, Husserl’s Dasein is no longer an ego, it is a Being as it is, thrown into an already pre-structured world, subliminally colluded with .
So there is no primary, conscious idea of the self, or self consciousness , and this idea is easy to miss and caused a lot of intricate search for the truth.
So the idea of alienation from one’s self and inauthentic ideas of the self is basically based this misapprehension,
aided and abetted by a Church, which had a lot to loose along the way.
I will get to the points You are raising, in due time, sans the promised reference, since that may be superfluous in such a broad outline.