Fuck The 100. After hearing good things about it, I was going to give that show another try after watching and disliking the first four or five episodes.
But not with storytelling like that.
BTW, The Walking Dead has a storyline with a well-developed and interesting lesbian couple who did not die right after consummating their relationship — and has gay male characters (Aaron and Eric) who are also really well-done, buy they are more in the background as compared to Tara and Denise.

Bad writing, The 100. Very bad writing.
(Yes, I know there was an earlier TWD lesbian character played very capably by Juliana Harkavy who was killed — but everyone dies on TWD. Everyone. It’s worse than Game of Thrones. And it was a pity, as she was one of my favorites of the side cast — Harkavy played her wild and loose and all chopped up inside, like the world she inhabited.)