Hurin and despair

[Numenorean]

Sorry for not letting this aspect of the thread die out, but when Morwen said:

Turin *chose* to take the actions that led to Saeros' death

and Saucepan followed with:

I see no reason why the curse of Morgoth, once pronounced, should not affect Hurin’s kin wherever they might be, even while they are in Doriath

It got me thinking about a couple of things in the Narn that could also be relevant. In his youth Queen Melian the Maia watches over Turin and sets another to do so in her absence, Nellas. Why though? Wasn't Doriath safe for him? Did Melian perceive that the curse would find a way to reach Turin, even within her protected realm?
Given the actions and behaviour of Saeros, she was far-sighted to do so. Which of course leads me to Saeros. What the hell was he on? By all accounts he treated Turin with nothing other than than contempt throughout his formative years. It amazes me that Turin held himself in check for as long as he did, even so "...the silence of Turin displeased Saeros as much as his words" So whatever way we look at it Saeros was out to mock and injure Turin. But what was his black motivation, maybe because he (Turin) was a kinsman of Beren? That seems too loose an association to warrant such 'veiled malice' against lets face it, an innocent youth.
The words of Mablung after the Saeros/Turin dinner table confrontation - U.T (P.81)- offer room for speculation:

...if either be slain it will be an evil deed, more fit for Angband than Doriath, and more evil will come of it...I think that some shadow of the North has reached out to touch us tonight. 'Take heed Saeros son of Ithilbor, lest you do the will of Morgoth in your pride, and remember that you are of the Eldar.'

Saeros of course heeds nothing and instead tries to kill Turin in cold blood from behind, no warning or honor, just a dirty sneak attack that does seem like he is doing the 'will of Morgoth in his pride'. Saeros activated a dark chain of events and brought his doom on himself, but more so on Turin, Morwen and Nienor. Which takes me back to Nellas the maiden, if she hadn't still been watching over Turin, the whole sorry Saeros episode would likely have never been fully explained, and Turin thought guilty of baseless murder. Did Melian therefore forsee that the curse was always going to find its mark, even in Doriath?