In all honesty, the last scene demonstrates some fairly unsettling truths about human beings. Blanche is shown to be tattered emotionally, depending "on the kindness of strangers" and going off to her own doom, taking long strides in the process. The poker game between the guys goes on, and while there is a bit of an outrage, no one says or does anything. Stella recognizes that committing her sister to institutionalization might have been a mistake, but she is cooed back into submission through Stanley, who is the "winner," but if he is the force of victory, humanity's redemption is in trouble. The reality brought out in the last scene reminds the viewer/ reader of the lack of totality or overall redemption within human consciousness. It is Williams' stinging coldness in the last scene that forces the belief that if "life continues," it might do so at the cost of specific individuals. There is an ending, not a good or bad one, but rather a cold one, reflecting what Williams might see as the root of all human interaction.
There has been an undeclared war going on between Blanche and Stanley ever since they first met. The war between them is over Stella, who would be called the MacGuffin in Hollywood parlance. Stanley acts like an animal. Blanche acts like a Southern belle. But they both know each other and what the issue is that is at stake. Blanche wants to turn her sister against Stanley and get her to leave him in spite of the fact that she is pregnant. Although Blanche acts sweet and gentle, she is tough and aggressive. She goes after Mitch, even though she doesn't love him, because he would make a good provider. She despises Stanley but fears him because he can see right through her. They are engaged in a dog-eat-dog battle, and she is destroyed by Stanley because he is stronger and because he has an hold on Stella which Blanche is helpless to overcome with allusions to their past gentility and storybook lifestyle. The viewer naturally cannot help feeling pity for Blanche when she is destroyed, but cannot help respecting Stanley for defending his home and family against a hostile and unscrupulous intruder. The people who built Belle Reve did not get their land and wealth from being refined and cultured; no doubt the early ancestors of Blanche and Stella were not unlike Stanley Kowalski.