Hi Henriette,
I guess if your partner's work is providing accommodation then you would manage on 55k. After that, if you are renting you are probably talking at least $350 p/w rental for Wellington and maybe $250 for food and general living expenses, so you might have to tighten your belts a bit. I'm sure you would manage though, particularly if it is only for a short time until you rejoin the workforce. If you have PR then you would probably qualify for Working for Families which would help considerably while you are not working.