Maybe I am just a masochist. (Forthright has suggested this in another context). In Tears of the Fallen Inuyasha dies for Kagome so even though he does not end up with he does die a heroic death giving up everything for her.
In Vying for Dominance he has to face an opponent he cannot beat without Tetsusaiga. He does so as Kagome's champion even though Kagome has already chosen Sesshoumaru as her mate. I have always been a sucker for medieval courtly love. (MA in Medieval European History) Those knights wrote poetry for their ladies(married to someone above them.)and fought for them, but in the end society would not allow them to be together.
As far as Sesshoumaru goes, I do bring some personal biases. Being male hetero I feel no romantic impulses towards him. When I first saw his picture I thought he was a woman. He reminds of all I ever disliked about one of my brothers who was always perfect (perfect score on SAT's, PhD in English and Philisophy and Senior Master in chess)

I have almost no interest in the S/K romance in these stories. I started reading them so I could vote on IYFG. They bring a different feel to Inuyasha than you will find in I/K. When S/K authors treat IY well I do not
find the reading stressful at all

I just finished reading all of the Harry Potter books. What struck at the end when Snape's role was finally revealed was that he was one of those tragic heroes who did what he did for the love of a woman (Lily) he could never have because of what Voldemort had done to her.