I have a side take on this.
Hating her completely doesn’t make sense, given what she’s done for him. But you can get angry at her for her lack of tact.
It’s like Subaru at the Royal Selection arc. We can sympathize with him because we know his actions stemmed from fear and trauma, but we can’t say that humiliating himself and acting like a jerk was the right thing to do.
That’s what makes Re:Zero so good. Its gray characters—you might love them one day and want to slap them the next.