A few days ago, I was walking alongside the Thames with Mr SM and the three children, pointing out (as I do every time) Big Ben and the Houses of Parliament.
We'd been to see an amazing art exhibition featuring life size models of the Marvel Superheroes constructed entirely from Lego.
We walked past the skateboard park, decorated with incredible (legally applied) graffiti, human statues, street magicians and acrobats and a street food market offering food from every continent.
I thought how incredibly lucky we are to live in such a vibrant city, a melting pot of different cultures, where astounding modern architecture buts up against beautiful historic monuments, and where every street has centuries of tales to tell.
Then yesterday Mr SM was crossing London by tube for a meeting and cursed as he approached Westminster and discovered that the tube line was closed.
He had no idea that just a few feet above his head four people had been killed and around forty injured (including three French teenagers on a school trip) by a terrorist ploughing his 4x4 car at around 70 miles per hour along the pavement of Westminster Bridge, then plunging a knife into a policeman outside Parliament.
In just a few minutes lives were lost or changed forever, and the ripple effects will continue as livelihoods are affected by reduced tourism.
It's really easy at times like this to want to hunker down, to stay safe, to cancel trips and change plans. But that's not the right thing to do. Because what yesterday really shows us is that life is short and the future is unpredictable.
We have to make the most of every minute. And we can't let the bastards win.
Love SM x