How can people actually like yagami light?

I liked him when I first started watching death note. He was pretty good in first few episodes but then he literally cracked. It's not even about his ideology anymore. (I don't agree with his ideology as well but that's not the case) He's not a healthy human-being. He used EVERYONE. He was even considering killing his own sister. And the way he knelt on L's grave?! It's disgusting. Imagine how great it would be if he was like "It was great competing with you but you were the one I had to get rid of to make my goal come true. I'm glad you were my rival" or Idk something like that.. I'd definietly liked him if he was that kind of person