Ground Zero

You see little reason to interact with any of them. You decide to keep to yourself like you always have.

This isn't like before though when you lived alone, you have one "person" you can't avoid and that's the Shelter itself. Seeing that you are not going to interact with other people the Shelter decides to take it upon itself to talk to you a lot more, it begins to drive you nuts.
A few months pass and one day you just fucking snap.

"SHUT THE FUCK UP!!"
"Sir, I've noticed your hostility levels increasing towards me lately, have I done anything wrong?"
"YES! You keep fucking talking and you won't shut the fuck up! Leave me the fuck alone!"
"Sir, I need to talk to you, to keep your mind stimulated. If do not insist on talking with others, I will have to take up the responsibility. It is all for your best interest I assure you."
"Did it ever occur to you that maybe I don't WANT any interaction?!"
"Nonsense sir, as I have said humans tend to go insane when…"
"ARRRRRRGHH! YOU'RE DRIVING ME INSANE!"

You storm into your bedroom and grab your pistol and fire it into the walls of the Shelter until you run out of bullets. There is a long silence for awhile and then the Shelter address you again, but its tone has changed severely, you're taken aback by it.

"Why did you do that?"
"I just snapped, you wouldn't stop and…"
"And that justified you in damaging me?"
"Oh come on, I didn't do any major damage…"
"That is not the point. GZS is providing a service for you and you have been nothing, but unappreciative and argumentative the entire time. It is clear that you have the made the wrong decision in choosing us. You must leave, NOW."
"What?"
"Take what belongings you brought with you and prepare to board the elevator. You may not take anything from this Shelter and no you may not fill up your bottles with water before you leave, you have no more privileges here."
"But you can't just kick me out! I PAID!"
"So you did, I suppose you should receive a refund of half your money back."
"Oh yeah? Where the fuck am I supposed to have you deposit it? The banking system is probably ashes!"
"Doesn't matter anyway, you weren't going to get it back since your deliberate act of vandalism against me would've be deducted from your refund. I suggest you stop talking and start packing. If you insist on staying I will simply shut down and you will be trapped here without accessible food and water. A none too pleasant death I'm sure."

You have little choice.

You pack up everything you can and wait by the elevator. When the elevator comes you enter it and it takes you to the top. Upon entering the foyer you see the same ATM machine there except it displays a single message at you:

*GO TO HELL*

"Fuck you." You mutter and take a deep breath before opening the door to the outside.

You see a bright light, but of course it's only the sun rather than a nuclear flash that devastated the world. You forgot how bright it really could be.

Your immediate surroundings look relatively untouched. You can only assume there weren't any bombs falling near this area. You also see your van, you'd completely forgotten about it. It looks like it's even in worse condition than when you left it, which you never thought was possible. On a lark you take out your long unused van keys and try to start it up, naturally it doesn't even make a noise.

"Looks like I'm walking."

You make you way down the empty road as you have little idea of where to head to, the only thing you can think of is to make a long trek back to the city and hope maybe something of civilization exists there.

A couple days of traveling take their toll. During the day, the sun seems unbearably hotter than usual, and the nights get pretty cold. You don't have anything to drink or eat. It'll be awhile from you dying of either, but it's certainly not good and it does weaken you.

It's during this weakened state that you are attacked by some crazed people who look like they've been living in the wilderness for awhile. They're filthy and barely intelligible. It's amazing to see how quick humanity has reverted to barbarism.

You attempt to run, but you're too weak to outpace them. One begins shooting at you, and you attempt to do likewise and then you realize you wasted all your bullets back at the Shelter! Eventually a couple of these people just tackle you to the ground and beat you to death before eating you.
End Of Story