I think Nathan isn't wrong to feel desperate at the age where puberty begins to leave its most damaging marks on our bodies.
With progress, comes higher expectations, and that's a good thing. Much like how the UN recently declared internet access to be a basic human right, I think pre-puberty medical intervention should be the ideal to strive for with what we now know about the pre-natal biological causes of a transgender identity, and the devastating effects of leaving it untreated.
If we didn't all demand and fight for more recognition and rights, we would all still be late-life transitioners. In a way, us older transitioners had the bliss that came with ignorance, when we believed what society told us, that our identities were wrong and that we could be "fixed".
Nathan is young, and aware of what's now possible with medical science. He's in a place of desperation and despair as he watches the first signs of puberty begin to take effect while knowing it doesn't have to be this way.
I think the best way to support him is to hear his grievances without being dismissive, and to offer helpful advise and assistance, as much as is possible online.
Nathan, where are you located? Depending on where you live, you may have access to psychological or medical help, and those of us familiar with your local laws could weigh in.