Theory on Patrick Bateman's insanity and it's role in the movie

Today, i've finally watched American Psycho, a classic movie who went popular these last years because of it's iconic lines added to the main character, Patrick Bateman, qualified as a 'sigma male' by the community. Personally, being a big enjoyer of psychological horror, i liked it very much. Besides the sex and the blood, it was a great psychological horror movie. One of my favorite scenes must be when one of the girls he brought back home tried to escape after she saw him murdering another girl. The camera's movement, the color of the walls and the way she screamed when she was running away was so well made. I liked the parallels they made in the movie, switching from a peaceful moment to an abundance of screams. I also want to make a constructive critique concerning the movie : unfortunately the end wasn't the best. I wanted the main character to actually do something. Idk maybe if he killed himself it would've been meaningful? : as the guilt of all the murders and crimes he committed eats him away after finally becoming conscious of the gravity of his actions, he decides that he no longer has the right to be alive.

Maybe if we knew more about his past/if we knew more about his way of thinking, it would've been even better. Personally, with psychological movies like this one, i tend to always make theories because of the lack of explanation at the end. It's always this way, at a point where it becomes repetitive and boring. I like it when there's a plot wist, an actual explanation to the behaviors taken all along the movie.

Well today, i have a theory. A theory that could explain the meaning of this movie in a deeper point of view : What if it was all in Patrick's mind? What if the whole movie only pointed out Patrick's extreme insanity and sociopathic behavior, his madness, in another reality which is his mind?

To prove my theory, I will firstly recall the scene where he was taking pills. An important information who suggests the possibility of my theory being correct. We also saw how he tries to hide/ignore his illness by having a perfect life, but was it even that perfect? we saw the drawings at the end that Jean discovered in his books : women decapitated, their naked bodies displayed with chainsaws deep into their flesh, and by that, we could unsure a theory that focuses on the imagination of the main character, a delusional type of imagination. Also, remember the scene where he called that girl with porn in the background? i would say by consuming so much of it, he could actually project himself doing everything he saw.

Why am i supporting the idea of it to be all in his imagination ? Firstly, we'll start with the end actually : he tells his lawyer that he killed Paul Aullens. The lawyer takes it a joke. We know that he "killed" him, but the lawyer still thinks it's a joke because he says that he just had dinner with him twice in the past 10 days. Secondly, how everything goes his way : ofc, in the whole movie, there are things that go against his will, because the movie itself is a mix of his delusions/excessive imagination and reality, so at moments we don't really know what's actually happening. Finally, how he described himself at the end, how he actually realizes that he's mad, insane. To summarize it, with the help of many hints in the movie we can assure the fact that he has a mental illness, a psycho ofc bcs of the title (wow CLEARLY didn't see that coming) and the end ofc. I have more to say but i'll wait to explain my point later. So i don't forget i'll give myself a hint : the detective and the reason of his visit.