Firstly, I have to answer the Thingol/Doriath question. It says specifically in Silm. that it was when he asked Beren to bring back the Silmaril that Doriath fell under the doom.
The sindar were cursed because they had contact with the noldor, and the same goes for the edain. The avari, well... wouldn't you be tired after living for 100,000 years?
