WPA2 password ?

I don't understand your problem. If there's anything Apple gear does well, it's wifi. Do you have your Airport set to hidden ssid? If so, make it visible. Then click on your ssid from your wife's iphone in wifi setup and enter the password carefully and correctly. You might even try setting a temporary dumb down password like 123 just to prove it works. Then go back to your more complex password and keep in mind that if you have a lot of _ or other special characters, it takes TWO shifts on an iPhone keyboard to bring those symbols up. Also keep in mind you must shift for each capital letter and the iPhone keyboard won't switch from lower to uppercase on the screen. This makes it much harder to correctly enter a password. Lastly, turn off that damnable iOS autocorrect. It's so clueless, it capitalizes the first letter of Passwords for you which is tough to spot since they are shown as dots on the screen.

For example, your ssid is zoo and your password is monkeys:

Pick the ssid called zoo and type monkeys. Chances are you get Monkeys and you can't see it because the letters become asterisks as you type them.

 

i always find a way to copy and paste my pwd rather than retype it.

for example i saved it in a draft gmail and accessed it that way on different devices.

obviously you need a non wifi access method to get it - ethernet for non portable devices, 3G for mobile etc

 

ah ok iirc mine is around 25-30 chars - so a bit harder to type without mistakes