My theory on this movie+ ending (spoiler)
Elly did NOT die. "a bitter end is better than endless bitterness"..she agreed with this statement. This is the focus of the entire thing.. she ran away from her fiance, because he was controlling and perhaps abusive. In her mind by doing this the "end" would be bitter for everyone, but better than having to deal with him.
Also, perhaps her so called fiance was just her boyfriend she wanted to run away with? so he wasn't her REAL fiance.. Thats why he took her bag with him. And didn't phone her parents.. because they wouldn't know who he is.
^Others have mentioned this too.