Some very thoughtful advice here.
I think you have to cling on to the fact that no one can reasonably expect to stay heartbroken forever, in just the same way that no one can reasonably expect to stay deliriously happy for ever.
Extreme states of emotions just can't last. Mother Nature is very wise and has designed us to only be able to sustain such extremes for relatively short amounts of time.
So, I promise this too shall pass. And one day you will feel a bit sad precisely because you don't feel sad anymore - and you will realise that what once seemed an all-consuming, heart-breaking emotion has just kinda faded away...and you simply forgot to feel sad because basically you were busy getting on with life.
In real life no one sits like Marianna in the moated grange pensively yearning her lost love for years and years. Life doesn't let you. No matter how heartbroken you feel life eventually takes hold of your hand and makes you walk along with it again. And every day you will be walking further and further away from this horrible, horrible today.
Definitely advocate a spot of re-decorating this weekend, even if you just re-paint one wall and buy a scented candle. Join an exercise class (my friend got dumped by her ex, joined a cycling club, and 2 years later is now engaged to a fellow cyclist
). Try and see your child-free days as an adventure where you get to actually be you again, and not just Mummy.
I think it important to make small but discernible differences to how you are now as opposed to how you were with him. It's an important emotional divide you need to make.
So wear a shade of lipstick you've never worn before. Read a genre of book you've never read before. Wear your hair differently. Go and see a film you wouldn't normally choose. Take the train to a city you have never visited.
You're not re-inventing yourself, there's no need as I'm sure you're already lovely as you are. But you are exploring yourself, and who knows what you might find once you allow yourself out of your comfort zone.
Good luck, and you will be absolutely fine, I promise.