Why lock down the thread?, that was a serious question,
they are talking all the time like there was a big dispute between them and riley brings her a gift etc. tries to win back her confidence etc. it looks more than just a relationship between best friends, also there is a scene where they kiss each other on the lips and it looks a bit sensually not like a kiss between people that are just firends.
I mean that they were a couple before the "Left Behind" DLC. Sry I am no native speaker as a German so my English is not perfect.
But even if Riley died it stays relevant, since the game is strongly story based, the fact that Elly could be homosexual is a interesting theory.
Of course it is just a assumption of mine, but I thought that way even before i played the DLC and after the DLC i am almost sure that Elly loves women.
Yes because it is not the single player section, but if you say that because you think its nonsense you must be blind and ignorant, ND are telling story's, you must be really blind that you dont have to think about that topic, after playing left behind.
I found this article with an interview with an ND developer and he confirms that Ellie is in love with Riley and that Left-Behind is an romantic story.
My guess is the relationship was ruined cuz one of em died.
That's definitely grounds for a ruined relationship.
The whole thread is a big spoiler already, so i might just add my opinion.
It's not really uncommon if children or young teenagers kiss to show her love without being gay. I never thought more than friendship when playing the dlc tbh. It was just a very emotional moment. In general, kissing means "love" first of all, not necessarily "sex", if you know what I mean.
*EDIT* Also Ellie talks about Riley as her "best friend" during the whole (main) game, she never indicates that there was more than (really good) friendship.