I've been there.
Being betrayed and left is shite, it's a loss and having to sit with that is hard. The person you took a chance on to have children with hugely let's you down and it's a wound. And then you have to parent on your own with that wound.. tough!
You are grieving.
Take it one day at a time, 3 meals a day, a wash or shower a day, clean clothes, gentle activities with the kids colouring etc (not sure the ages). Try and move your body once a day.
You are allowed a space to take it easy. 🌸
I think some people seem very lucky in that they pick "the right one" who will stick by them and so on. Others aren't so lucky and we learn too late...
I think reaching out for support if you can is important even if it's just someone to come over and have a cuppa with so not just you and the kids.
I agree you sound depressed so looking into support for that could be helpful. Some counselling and perhaps medication if you are open to it. Loss is a huge trigger for depression.
Take it easy and I hope things get a little lighter and brighter for you my love.
What I will say is although for me being left was hard, it knew actually in retrospect the relationship was not healthy and it's given me time to reflect on that and think about what I need in a husband.
Take care 🌸