One of the amazing things about humans is we have this ability to think about how we see ourselves. We call it our identity.
So many different things go in to making up our identity: What colour we like, what foods we prefer, whether we like pineapple on pizza, what activities, sports, careers we are good at and drawn to, who we are sexually attracted to and, perhaps most fundamental of all, what gender we consider ourselves to be.
You only have to watch and listen to young children playing and talking about other children and adults to understand how fundamental gender - boy or girl, man or woman - is to how we see the world.
But for some, the gender they identify as is different to their biological sex. It's not a new thing, but our growing understanding and acceptance of individuals' right to define their own gender identity is.
In part that's because we now understand how much damage crushing people's identity does.
I'll be the first to admit that psychology and psychotherapy hasn't had a great track record when it comes to understanding sexuality and transgender issues. Psychiatry only officially stopped classifying homosexuality as a disease in 1973, and until very recently "Gender Identity Disorder" was technically a psychiatric diagnosis.
We know that people's experience of having their natural selves invalidated, be that by their family, or society more generally, can have fatal consequences.
Nowhere is the struggle for identity more real, and more visceral than adolescence. And at no other time is the experience of our gender becoming obvious and, for the first time sexual.
It's little wonder then that teens who identify as transgender can struggle so much. The New Zealand Adolescent Health Survey (2012) reports depression rates for teens who identify as transgender is around 40 per cent. Nearly half had self harmed in the previous 12 months and 20 per cent had attempted suicide. This is massive compared to the rest of the population.
When we crush someone's identity, we crush them. The experience of being not able to naturally express who we are is one of invalidation: We feel as though what we think and feel is wrong, and that therefore who we are is wrong. Policing people's identities just doesn't work, because it creates another very dangerous problem.
When we invalidate someone's identity, especially something so core to their identity as their gender, we kill their spirit. It makes sense that someone then feels the next natural step is killing their body.
So don't for one moment think this is just about bathrooms. This is about allowing people to define their own identity, to live to their full potential and to be fully themselves, safely.
Where to get help:
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• The Word
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• CASPER Suicide Prevention
If it is an emergency and you feel like you or someone else is at risk, call 111.