Well M-K....if nobody ever felt not okay what kind of world would it be? We'd all be walking around smiling even though we're dying inside. Or worried, or sick, or angry, or scared.
Find your 'not okay' and treat it as an oasis of calm where you can retreat, knowing you need space. Have a room you can go to, or sit in the car, or write stuff down, or talk to a friend. You can even be 'not okay' when you're sitting in the same room as him because eventually I hope you'll be able to separate who you were from who you have to be.. now the dynamics of your life have changed.
I found when I was 'not okay' the best thing to do was something physical, just to counter the
ever-churning thoughts in my head.
Be well
Elle