I'm sorry you're sick, it's hard to be sick and sad too.
Are you caring for all those children? That's quite a load when you're sick. Do you have family you could call to help you right now.
The fact he ditched is not surprising, in active addiction it's always "them first", but it's a shame that he couldn't stay clean long enough to help you out.
Maybe this is a strangely wrapped gift that will give you time to decide if this is how you want to live.
Prayers out for you and your children.
Hugs