hey there!!
just wanting to help you a bit.. i havent applied for pr for nz myself but did for australia through my ex partner..
we hadnt lived together for a year at the time of my application, i was only a few days short but they asked if we had been living together before and i said that my partner lived with me and my family for a few months every year so they just asked me to get my parents to write a letter saying that we lived at their house together and that was good enough for them.
I guess that s all you can do really.. dont you have mail that went to your moms address as you had both lived there? you dont have to give them all the things stated on the website, they are just a few suggestions and you hand in whatever you have.. the bank account and flight tickets are definatelly good.. i always kept flight tickets as well and it got me a long way
since you have been living together for that long you should definately apply for pr
it all seems very confusing but it s quite straight forward. you fill in your forms, get your medicals and police checks and all the proof for your relationship
this page states exactly what you need to hand in
Steps to apply
good luck!