LAHABREA
Athena cared naught for Erichthonios, beyond how he could serve her ends.
You claim to be acting in his interest, but 'tis plain you are no different.
As I ushered Athena to her end, I vowed that my sole mission in life would be to guide this star true.
In service to that vow, I silenced the whispers of my heart. I could not nurture a son whilst an entire world looked to me for guidance. For that choice, I bear the responsibility...
Yet he is still my son, and I'll not suffer you to seduce him with false hope. You, who are naught but the bitter dregs of Athena and I─the very worst of us!
Having tracked down that quote, I also see he alludes to having killed Athena, but that's still light on detail.