*Suddenly* Wifi Won't Connect?

Hi there onmore4gsus,

It sounds like you've done quite a bit of troubleshooting but you're currently unable to connect to your home Wi-Fi network on just the iPhone, whereas all the other devices work fine. I really like the way you outlined your troubleshooting, that's fantastic! Next I would quit the Settings app:

Force an app to close in iOS
https://support.apple.com/en-us/HT201330

1. Press the Home button two times quickly. You'll see small previews of your recently used apps.
2. Swipe left to find the app you want to close.
3. Swipe up on the app's preview to close it.

When you have done that restart the device and your modem/router and test the issue again once everything is powered back up and all the appropriate lights are lit:

iOS: Turning off and on (restarting) and resetting
http://support.apple.com/en-us/HT201559

If the issue persists that tells me there may be an issue with the iOS installation, so backup your device to iTunes, then restore it as new and verify that it works.

How to erase your iOS device and then set it up as a new device or restore it from backups
https://support.apple.com/en-us/HT204686

If it does work as expected when restored as new, then restore your backup to either verify it still works and the software just needed reinstalled, or isolate the issue to the backup file itself. Thank you for using Apple Support Communities, let us know how that goes!

Even if your other devices can connect to your network, please restart your router. It may solve your issue.

What happens exactly when you try to connect to Wi-Fi? Is it greyed out, or dim? Do you see your network in the list? Does is say it's connected but can't access the Internet?