I usually go with the reading that Mordred was yet another "orphaned" child in the stories. The theme repeats over and over - feelings of illegitimacy and the desire to overcompensate. There's a nice book out, modern, that shows this. It's called The Winter King by Bernard Cornwell. The thing that makes this book interesting is that Cornwell was an orphan and recognized certain similarities between his desire to please and Arthur's actions in the earlier stories. My mother was an orphan too and once it was mentioned and I started thinking about it, that reading seems to make sense.

That said, Mordred is a victim. I would say his mother dehumanized him but, in the strictest sense, did she ever think of him as human? He was a tool, a weapon, against Arthur. He was payback against Uther and possibly Ygraine.

I suppose that wasn't such a big deal back in those days. Children meant hands to work the farm or helpers in the shop; they meant prestige in number and in sex. It was a duty to produce children. Mordred was Arthur's only child - he never had a child with Gwenivere, their marriage was impotent - but his child with Morgana was both outside of marriage and incestuous. A non-entity.