A common way to lose Dalia is waking her up in the morning, instead offer to make breakfast and it should work
I am not one to use walkthroughs until after, but maybe look up to where you are? See if you had an unsuspected fail much further back. If you go back... a year? I failed with Alex in .5 because I didn't say her pen looked great.
Pen-point accuracy VN's usually turn me away, but the story is just too good, OiaL as well