How is it that Curley's wife's dream in Of Mice and Men is delusional along with George and Lennie's dream? And how is it that the further away you...

Curley's wife is beholden to an apparently delusional belief that she might become a Hollywood film star. She never makes it to Hollywood and instead ends up marrying an insecure bully on a ranch outside of Salinas in central California, living an isolated life where she is by turns threatened and threatening in relation to the men on the ranch. 

She shares her story and her feelings with Lennie, expressing her sense of unrealistic hope and her view of her unenviable position on the ranch. 

"Seems like they ain't none of them cares how I gotta live. I tell you I ain't used to livin' like this. I coulda made something of myself."

She tells Lennie that she met a man at the Riverside Dance Palace who told her he would "put [her] in the movies" and said she was "a natural." While there is a chance that Curley's wife really is as talented and fetching as this story suggests, the more likely truth is that the man was lying about his own position in the film industry, lying about Curley's wife's chances of becoming a star, and merely trying to seduce the young woman. 

Despite the reasonable doubts about her potential that would seem to compel a fully rational person, Curley's wife clings to the belief that she both could have been and, maybe, could still be a movie star.

The scope of her delusion is clear when she expresses the paranoid belief that her mother has intercepted the promised letter from the man at the dance club that would supposedly invite her to come to Hollywood. This paranoid belief drives her to leave her mother's house and marry Curley. She explains her reasons, saying she "wasn't going to stay no place where [she] couldn't get nowhere or make something of [herself], an' where they stole your letters." 

The end result for Curley's wife would seem to be that her delusional dream creates a rift between her and her mother and leads her to marry a man she admits "ain't a nice fella."

In this way, her delusion creates her isolation, making her an unhappily married, friendless young woman on a ranch full of people prudently afraid to socialize with her. 

Of course, not all dreams are delusional. Even this dream may have some credence. There is some chance that Curley's wife actually could have become a star, but we can see some ways that her dream ultimately and ironically manifested itself as isolation nonetheless. Instead of becoming a famous star, loved by many, she is seen as a dangerous "tart" that people are frightened to approach. 

In the case of George and Lennie, their dream of owning a ranch may have been out of reach (and thus delusional) until they meet Candy. When Candy suggests that he can contribute real money to the project, George realizes that the dream may be realistic after all. 

The degree to which this dream of land ownership is realistic or not is disputed in the narrative. Curley's wife claims that it is a false dream. Crooks initially expresses skepticism. The odds are against success. Yet, the dream is not entirely impractical or out of reach until Lennie kills Curley's wife. At that point the vision of what could have been is shattered. 

When Lennie kills Curley's wife, Candy sorrowfully recognizes that the plan is now off and so is thrust back into an expectation of a bleak and socially isolated future.

George has to kill his only real friend and so is also now profoundly isolated. 

Should we blame the dream that these men shared for the isolation that finally defines their circumstances? Or should we note that, for a while, this ambitious dream brought them all together (with Crooks too) in a vision of hope and promise?

We certainly can see some exceptionalism in George's first speech regarding the dream that he and Lennie share (because this dream is, in part, what separates them from and elevates them over other ranch hands and migrant workers).

So, there is a way that the dream functions to isolate the pair early on. However, the importance of the dream of land ownership links this pair and the other men and the novel itself to an important idea.  

Their idealistic dream is eventually destroyed by an unfeeling, materialistic, modern society. The tensions between the characters are inherent in the nature of American capitalism and its class system.

The failure of this particular dream of land ownership is intrinsically linked to notions of social-political change. Their idea, as natural as it is, is revolutionary and radical. To achieve this dream, the men would be escaping and overturning an entire system of capital and labor relations. The fact that such a simple and natural dream can be seen as impossibly revolutionary is one of the book's most powerful messages.