When the bravest and most resolute among us says "farewell and thank you", it is a heartbreaking moment. Emma Hannigan, bestselling author of 13 books, extraordinary friend, mother, wife and person, posted last Friday that "time that I knew was borrowed must be given back soon, so it seems". The cancer that she has held at bay for 12 years cannot, apparently, be held off much longer.
It is typical of her generosity that she would allow the many for whom she is friend, confidant, inspiration, as well as the creator of wonderful books, know the place she is in. And the response to that knowledge - the thousands on thousands of messages of love and support to her and her family - is proof of just what a huge hold she has on hearts in Ireland and around the world.
To say she will be missed is a pathetic attempt to grasp the extent of what she will leave. There are not, never have been, many like her.
Emma, in the years that I have known her, has always been vivacious, beautiful and funny. Completely gracious and gallant; a delicate wisp of a girl, with adamantine will. She didn't just put up with the wretched things that happened to her; she refused, with sheer bloody-minded determination, to let them destroy her faith in life.
Emma has always believed in the power of humour, of kindness; of make-up and a decent haircut, and with those slender weapons, she has fought one hell of a fight - not just against cancer and all the wretched side-effects that come with it and the treatment of it, but also against the world's perceptions of it and people who have it.
Emma has never been 'a patient', never passive, never a victim. Instead, she has been the driving force in her own battle and, I have absolutely no doubt, as much an inspiration to her medical team - whom she once told me are "amazing; I let them do all the worrying and I get on with the other stuff!" - as she is to those of us who know, love and read her.
Ever direct, she has a deep objection to euphemisms of any sort, particularly when it comes to cancer.
People whispering about 'the big C', or referring to someone as 'not well' in a particular tone of voice, have always infuriated her, and she has done an immense and deeply valuable job taking that kind of shirking ambiguity out of society. "I would take my top off in the park if I thought it would help raise awareness among other women," she told me once, and so clearly meant it. Thanks to her, there are women whose lives have been and will be saved.
The first time I met Emma, she was temporarily clear of cancer after her ninth go of chemotherapy and radiotherapy - words that don't even begin to communicate all the attendant horrors of pain, nausea, infection and misery that are the backdrop to those treatments.
She was then, as she always has been, utterly cheerful. "Life is fantastic," she said, adding, with her particular brand of deeply mischievous wit: "There's no point in fighting to be well, fighting to live, and then being a miserable cow! Life is precious. Everybody has adversity, you've got to take it as it comes, but by God you've got to grab the good times and the fun, and focus on it and enjoy things."
And she did. Over the years, we were in touch more, striking up a friendship based on writing, parenting, publishing and a shared sense of humour (I never met anyone more determined to laugh at life's awfulness than Emma).
Then, in 2016, when I was diagnosed with cancer, we had that in common to some extent too. I say 'to some extent' because my brush with the wretched disease in no way came close to Emma's far deeper understanding of it, and I am still astonished that she had so much sympathy, practical advice and general cheerleading to spare for me.
I rang her, as so many of us have done over the years, with my bad news: "Emma, I've got cancer. What do I do?" Even talking to her for five minutes helped me. When I apologised for troubling her with my relatively insignificant problems, she waved me away. "I'm like a village elder," she said, laughing. Then, "You'll be fine. You can do this." And because she said it, I believed it.
Even then, I had no real idea of the full extent of what Emma lived with, because it was not her way to tell the many awful details. Every message I have from her is positive, full of belief and plans for the future.
Frankly, it was only when I read her wonderful memoir All to Live For, published last summer, that I had any real idea of the scale and scope of what cancer has done to her life.
But the point is not what cancer did to her life, it is what her life has been, despite cancer. If ever there was a model for how to live, it is Emma. "Faced with very little time, can I tell you what screams out at me? Love," she wrote last Friday. "Nothing else has much meaning any more. Just the love I feel for the people I hold dear."
She is a warrior, a Trojan; with an ability to fight that is born out of her great love for life, but also, mostly, out of her great love for her family - her husband Cian and two children, Sacha and Kim.
Nothing is over yet, and miracles do happen. I'm praying for one. But if the time for that is not now, then what is left to say is simply this: Emma, you are loved. You are magnificent.
You will not be forgotten.
Letters to my Daughters by Emma Hannigan, published by Hachette Ireland,£7.99, is on sale now
How Emma broke the news that time was running out
The time that I knew was borrowed must be given back soon, so it seems.
The conversation I never wanted to have has been said.
My medical team have thrown everything but the kitchen sink at this fight, but all avenues have now been exhausted.
To say that I am heartbroken doesn't begin to cover it.
But I feel I'd like to say something, after all that's what I've done over the years - say stuff, write stuff and tell you what's going down. So I feel it wouldn't be fair to leave you out in the cold right now.
I've gained such strength from all of you. We've shared tips and hints and stories over the years. For all of it - thank you.
Faced with very little time can I tell you what screams out at me? Love.
Nothing else has much meaning anymore. Just the love I feel for the people I hold dear. My two babies (ok they both tower over me, but I'm still allowed to call them my babies) my husband, my parents, my family, my friends and readers. Yes you guys are up there on the short list. You've been an integral part of my existence and have championed me and held me in your virtual arms.
The love in my heart is all that matters now. I am broken-hearted at having to say goodbye so if it's alright we'll say farewell instead …
Farewell and thank you, I am taking a bow.
Until we meet again may all that is good and decent be yours
Love and light