And my alternate version of Terminator: Dark Fate.
10 years after T2 and John is a young adult. Now that he will no longer become the savior of all humanity, he's just an ordinary schmo with no future working part time at a Bargain Mart in New Mexico, which he greatly resents and which causes him to become depressed. Now obese and unshaven, the only thing he raids is the refrigerator. Dani is the new employee where he works and he's smitten with her, but she hasn't been responding to his advances. Grace is her older sister and tells Dani that John is a loser and to stay away from him. He complains about this to an old chain-smoking Sarah, who is now bedridden and dying of cancer, and who falsely (out of intense paranoia) blames skynet for her ailment.
One day, while on lunch, John sees Dani flirting with the assistant manager (played Gabriel Luna) in the breakroom. After having a series a flashbacks where Sarah throws a plate of overcooked eggs at him while screaming, "How in God's name did you ever save the world?", John's mind snaps. He becomes convinced that Luna is a Terminator sent back through time to steal the love of his life, and make baby skynet. He calls up his weed dealer, a paranoid Rastafarian named "Dr. Big 9's", and asks for something powerful enough to whack his mother. After which, he can use the insurance money to make himself appear wealthy, and win Dani's heart. Because (as John puts it) "B*tches love 20's". Doc wants nothing to do with it, and tells John never to call him again.
Distraught and growing increasingly insane, John plans to steal guns from the armory and sell them on the black market. When he returns home to do this, Sarah's introduces her boyfriend Carl, who looks just like the T-800. Sarah is unable to recall this due to her advanced condition, but John (now convinced skynet still exists) goes into a panic and kills Carl. John then sits on the floor with his back against the medical bed, laughing hysterically.
The police arrive and arrest John. As he sits handcuffed in the back of a squad car, he sees Carl's body being wheeled out on a stretcher. Suddenly, a BMW pulls up, and Dani and Luna step out. Dani runs screaming towards the ambulance. Carl (as it turns out) was Dani's father. As John sits back in the seat and the police drive him away, he notices they have taken a wrong turn. John asks the cop what is going on, to which the officer slowly turns and replies, "it is nice to meet you". We hear John scream as the car drives off into the rainy night.
Spoiler
Alternate Ending
After killing Carl, John escapes the apartment with several firearms and forces Doc at gunpoint to use his connections to set up a meeting with Jack Welker from Breaking Bad. Jack puts him through a series of loyalty tests. Impressed with John's abilities, Jack takes John into his confidence. He tells John that as part of his new life, he must assume a new identity, and says John's new name will be Kenny.