Hello. I can relate to how you feel. I'm married to a Kiwi, although we chose not to have children as neither of us wants to be parents. (So, what am I doing on a parenting forum ? There's lots of chat threads on this very site about that as lots of contributors don't have kids for one reason or another.)
We lived in NZ from 2011 to 2016. Not in Auckland although that's where his mother and sister live albeit in totally separate districts.
I told my husband (we met in 1992), before we got married (in 1994) that I did not want to live in NZ and if he married me thinking I would change my mind that way lay divorce.
So, one day in the summer of 2006 (the fact that I was still reeling from my mother's death the previous September meant nothing to him) he tells me we could sell our house, move to NZ buy a house there and have a nice life. I was so surprised I pretty much said ok. No discussion, no agreement no nothing. The whole of the talking was how we were going to do it not whether we should do it. I didn't even have the courage to say can we just try it for a few years to see how we go.
I even had to work up the nerve, twice in fact, to ask him if he would claim his unemployment benefit when we got there because he worked in NZ prior to coming to Britain. Only as a last resort if things got tough when we were looking for work.
However, we moved in Feb 2011. About 48 hours before we left for Christchurch, NZ a huge earthquake hit the city. It was to late to change our plans. We had sold our house, resigned from our jobs, said goodbye to friends and family, rehomed the cat, converted our currency into NZ dollars.
We arrived in Auckland to visit his family initially like we said we would. That degenerated into an unpleasant saga and we couldn't wait to get on our flight to Christchurch a couple of weeks later.
To cut a long story short, Christchurch was a write off in all sorts of ways. Three months later my husband got a job on the North Island and off we went for our final throw of the dice/last chance at emigrating. Just in the nick of time as the money we had allocated ourselves to live on initially had all but run out and we were planning, on paper at least, to return to Britain.
Fortunately, it worked. We lived in a nice little coastal town. We lived in a nice house in a smart area. All good.
However, I could only get short term temporary jobs. I ended up doing voluntary work just to keep an up to date reference on my CV.
The friendships I have were with a lady from Thailand and another who was American. Kiwis are pleasant enough but don't make new friends easily, it's a two way street.
My husband enjoyed his job. We visited his family in Auckland two or three times a year. It was a day long drive but we did it.
He knew I wasn't happy. His job was getting stale so we sold our house in NZ and came back to Britain. I made sure I got my NZ citizenship before we left. I'm glad to be back. DH has said he loves NZ but cannot live there.
Can I ask you some questions please ?
What job did your husband do in Britain ? You did well to be able buy the Castor Bay house, pretty much for cash.
To what extent is your husband beholden to his family ? Do they have him by the short and curleys ?
Do you believe the family business has devalued by so much with the remainder still being owed to his parents ? Kind of convenient with a possible divorce looming.
Is there a cultural issue with the family ? What line of business is his family in ? Is it different to what he did in Britain ?
Why has he allowed himself to be drawn back into his family like this ? What are his priorities ?
Does he have any explanation why he did not call you when he was away for two weeks.
He seems to be in his family's thrall, a little to willingly. Why ?
Good luck. Take deep breaths.