Was it too late to realize that? All this time Castelia was too scared of Joshua to the point that she didn't even look at herself. Castelia always knew that Joshua wasn't evil from the start, his attitude was terrible because of the bad past that accompanied him growing up.
Often Joshua throws words and even hurtful curses. Sometimes they fight and Joshua often throws things he can reach and not least Joshua grips her arm too hard and stares full of hatred.
However, underneath all that, didn't Joshua also care about Castelia? Castelia remembered there were times when Joshua was kind and cared for her, took care of her and smiled even though it was very rare.