It's not every day you call up the mother of the bride to tell her that you're getting married in trainers - and that she needs some too!
After waiting 13 years for a proposal, I don't think my parents ever expected my partner and I to get married.
So imagine their surprise when I announced that not only would there actually be a wedding, but that they'd have to get up at 6am to be there - on the Cutty Sark, dressed to watch a marathon, that we would be running.
Three years ago, when Duncan proposed, I had visions of a Cotswolds country garden wedding with edible centrepieces and vases of alliums.
I didn't own trainers.
Having had my pelvis rebuilt in 2007 and pinned with metal, I'd never experienced the feeling of being alive (and completely shattered) at the end of a run.
But, being diagnosed with breast cancer, just three weeks after getting engaged (not to mention being told by your oncologist that you are likely to gain three stone during chemo) did a lot to change that picture.
I chose to run during treatment because I wanted to show my body that it can take a lot of things - forcing me to learn to walk again in my 20s and stealing my boob in my 30s - but that it couldn't define me. I chose running because I knew it would be hard. I chose running because I needed to find a reason to get out of bed and feel the sun on my face. I chose running because I wanted to feel alive at a time when my body had other ideas.
With my nurse mum as carer, Duncan could be my running partner (by which I mean running in the same races miles ahead of me). It kept us going when circumstances could have so easily ripped us apart. Running changed the course of my days and, in so doing, changed my life.
This is a hard post to write at a time when I can put on my trainers but I can't move forward. But, while I am injured right now and in the hands of surgeons and physios as they try to diagnose my pain, it is the dream of a cold day in April and the London Marathon that keeps me going.
When you've fought for your life, it's hard to plan too far ahead and rest your happiness on one day in the future. So, when we started talking about our wedding earlier this year, I knew there was only one way to do it. There wouldn't be an aisle. There wouldn't be a first dance. There wouldn't be a day in the Cotswolds.
Our wedding had to be a chance to give back, volunteer, thank those who have supported us and to remind the world that life may be hard but, by focusing on the little - and often beautiful - details of life, you can make every day count.
That's why the ceremony is happening at 7.30am and the honeymoon will be spent on the Great Wall of China.
I know wedding planning is supposed to be stressful, but I thought that by cutting out the favours and the sit-down meal and focusing on charity it would be a little less involved.
Not so. With road closures, a running wedding dress being designed by the incredibly kind and brilliant Frankie Seaman (Professional Ice Skater from Dancing On Ice), a hen 10k run and a gel bouquet all part of proceedings, I know this will be an experience we will never forget.
I know a hip full of metal, superglued stomach and tummy-fat filled right breast (from mastectomy surgery), oh, and asthma, do not the best running companions make. I know that my next run could be my last (I haven't ruled out walking it if I am not able to run again). I have been told - on more than one occasion - to find another hobby before I break myself completely (and I will if you let me run one more marathon).
But, when I'm running, I have everything to smile about and I certainly didn't beat a life-threatening illness just to play it safe.
Our wedding isn't just a celebration of love and life. It's a chance for us to thank the people who helped us find our way back to happiness both during and after treatment.
We also want it to serve as a reminder to everyone going through difficult times - whether it be serious illness, or loss, financial difficulties or the daily problems of life - that there is a way to move forward.
If you're reading this, you're already on the journey with us. Welcome to the team!
If you'd like to support us please visit: bit.ly/2eSLaed
I will be also writing about the big day and beyond on my blog thisdayforward.org and via Twitter @Jackie8.