What happens at the end of The Congress?

Here's what I think happened:

Remember when Robin was at the Congress and they were about to release a new chemical "product" that would allow people to "become" or "be" Robin Wright?

I think Robin's son left her a chemical version of him, and that allowed her to experience his life and memories from his point of view. That's why we saw when he has breastfeeding, when he was growing up, and snippets of his life.

We then see Robin looking like her son (which kind of explains my theory,) in the desert where another version of her son is flying a Wright brothers plane (which was mentioned during the film, when the boy speaks to the doctor.)

I think this is the final hallucination that Robin's son chose. He's the "first Wright brother". Maybe he left that to her mom so that they could eventually reunite, at least "chemically"?

I think both answers above have an intersection where they are correct:

Perhaps the drug she takes is distilled from the Son...in any event she does relive parts of his experience and she looks like him (clear from the reflection in the Airstream trailer). She is putting this out.

I believe the person she sees is a separate entity and is indeed her son for two reasons:

1) Who else would even know the Son to project his image to her? and,

2) Everyone chooses "what they want to be" and my experience of the character of the Son is that he was fine with who he was. He would project his own image, but idealized to his youth before losing his hearing and vision completely. This is why she sees his younger self and not the 30 year-old + version he would have been when she left him to attend 'The Congress' or the 50 year-old = age he would have been when he entered the pharmaceutical dimension.

Make sense?????

The son didn't leave a chemical vile of 'him'. Earlier when Jon Hamm's character was explaining the rules of this new world he said that the user simply imagines what they want to be.

regarding her Son leaving her behind the chemical to become himself I have to disagree because of two reasons:

1.) The Doc asked "do you know where you want to go?"

2.) The Doc also said the Son thought she wouldn't come back.

Because of that, my theory is the following: Similar to "Interstellar" its not really a story about reality or consciousness but in the very basis a story about the love of a parent or the bound between a parent and a child. Therefore and because of how the animated world works she decided to live his life again (because she was there for most of it anyway) and at the end the audience is left with the decision wether or not their bound is strong enough so they end up together in the same subconscious place or if its just a fantasy of her.

I also wanna state that a reviewer on rotten tomatoes put it best "The Congress rises on the strength of Robin Wright's powerful performance, with enough ambitious storytelling and technical thrills to overcome its somewhat messy structure."

The structure is sort of messed up (maybe by choice of Folmann or maybe by the editor - who knows), but for me Robin Wrights performance and also the basic Idea behind the movie (both the story of love and the bond, as well as the idea of a possible drugged up future - which also has a metaphysical element to it: just living in your own head and creating your reality) makes up for that. which leaves us with a disturbing and sometimes artisanal bad, yet powerful and beautiful movie.

It seems to be more of a pitch, then a fully completed work

one curiosity of the scene where she rejoins the real world. As she leaves behind Dylan, she walks away glancing at the guitar player who gives her a curious look. I have pondered what that meant and wonder if that person was indeed her son. This would of course mean that when she meets Aaron in the desert it is only her imagination and desires not the Aaron.