Honestly, people think that Yuno is a crazy bitch but that's only because she only has one dream to look forward to, and that's being Yuki's wife. I really wish that she found someone else to "look forward to". But, now, since she's in "love" if anything happens to Yukiteru then everything will basically crumble.
That or she commits suicide. But, I'm thinking she'll first kill then kill herself.
Beyond that point, I don't know who to feel sorry for. I mean, Yukiteru is a coward. However, as stated, he said that he is just a "bystander" and I think that's what a majority of people would do. Use others for their well-being, it makes sense, people still do it today.
I have to say, Yukiteru is certainly different from other manga characters who always come out to be the "hero" and it's a nice change of pace from "oh, no; that woman's in trouble, let me help her!" to "oh, no; that woman's in trouble! I wish I could do something!"
Usually, you see that from minor characters in other series but... Yukiteru's another story. Anyway, I can't wait to see what happens next.