My father lost mum when he was 64, she 62. I thought that was pretty cruel. But then I lost Deb when I was 63 and she was only 57. And I found myself living alone in a foreign country, with all the ghastliness of sorting a funeral, probate-equivalent and lots of other tedious and mysterious admin. Evidently I coped, but I lost weight (I have never been overweight in my life, so this mattered) and was a bit of a zombie for a while.
There are no clever cures for the loss you feel - and when you spent a lifetime together his presence made everything easier to cope with. Now you must do that alone. I won't patronise you by telling you to get out more, or to seek friends to support the worst days, or anything like that. I can tell you it does get better, but only you can handle the dark and the drear.
Be strong, and one day, maybe not for a long time yet, you will see a ray of sunshine again, and then another and another. I promise it will happen.