No wonder you feel so sad. I don't know how you have coped with so much tragedy. I'm so sorry you are having to suffer so much.
Having three kids is both a help and a hindrance isn't it. They can keep you rooted but take a lot of energy. Sometimes it's hard to be strong even when you need to be.
Since you can't afford therapy maybe the helplines can offer a bit of comfort. There's a long list of help numbers in the resource thread at the top of the depression forum. Like someone said, sometimes you may get someone who isn't helpful. Just hang up and try again later and maybe the next person will be who you need them to be.
In the meantime, we are here for you. You have our attention and our support.
I hope you can be better soon