Diane was haunted by demons, severely depressed and had a personality disorder. She was traumatized as a child which is what I think the creepy old people were all about. I think Diane was tormented by all her demons and she was trying to put everything together to make her self feel complete and live the dream she had always wanted to. She wanted to have control over her mind but she could not get rid of the other personalities or you can say demons. I do not think she was just in love with camellia as a person, but she was even more in love with the life she had.
The whole first part of the movie is not really Diane having a dream but it was just an example of what was going on in Diane's head and the dream she wanted to live. All of the crazy characters like the cowboy, the guy in the chair, The agents were all different demons of Diane's personality. They are the ones who had the control over Diane's mind. The blue box represented Dian's soul. The demon at the restaurant was the demon that had the grip on her soul. The woman in the theater was Satan and had control over everything. I don’t know if Lynch is spiritual but these are just my thoughts so bare with me.
When Diane woke up that’s when the reality of the movie started. She was in love with this actress but also extremely jealous at the same time. She wanted her life more than just being in love. All of the demons that were haunting Diane were driving her to do the unthinkable and commit murder. When Diane was in the restaurant and gave the guy money. I do think she was giving the money to have her killed. This is what the demons wanted and part of satins plan. When the guy gave her the key and told her after it was done she could open the box or what ever. That was just an example on how Diane would get her soul back after the murder was over with. Its kind of like the devil giving you something as long as you do something bad for him. At the end Diane found that she was not released but only fooled by satin and she was driven to kill her self. To put it short. The price she paid for killing someone pursuing the dream she wanted to live. I think this movie was an example on how people are driven by temptation and greed to do horrible things by evil and when they commit acts as in killing for money or killing because of jealousy. Something always goes wrong. It is always a lose, lose situation when you commit evil acts.
Just my thought and I had fun trying to figure this out and writing it.



