Char was the one who told him to be obsessed with her in the first place so she can't complain now. I also feel like he was sort of doing her her a favour. Personally, I felt like Char would try to end her life or something if she killed the Emperor. I also feel like killing him would have been too easy a punishment. He wouldn't have to suffer what she went through so if Dylan really did give what I think he did then I'm more than happy with it.
YOU were the one who wanted to divorce Navier. YOU were the one who brought in a mistress. YOU are the one who broke her heart first.
Seriously, what gives you the right to be mad she got married immediately right after the divorce. You lost your chance the moment you trusted that slut over your wife who you've known since you were young.
You /had/ your chance and you CHOSE Trashta. Reap what you sow.