Feeling Like a Failure

I have been sobbing on and off for the last hour. I am certain some of it is hormonal, but it doesn't make the things I am feeling any less legitimate. It may just effect the way I manage those feelings.
I feel like a failure.
My oldest child is going to have her last "childhood" Christmas with us, and I am going to scrape to be able to do anything for her.... I know I should be thankful that I can give her something - but I think about the day she was born and how I wanted to do well in life - for her sake. I wanted to give her so much more. Not materially - but a full life. I just wonder if she's had it.
The younger two are pining away for West Virginia - and the friends and good times they knew there. Cookie baking days, Christmas parties, making gingerbread houses, shopping trips, ornament making, hanging out with friends for long winter days while the moms Christmas shop together - - and I don't know when or if they'll ever have that again. I have tried to muster up the energy to plan some of those things here - but I am really struggling and can't seem to plan a thing.
The larger these feelings get the less functional I am and the worse I feel.
I feel like a spectator in the lives of others, from a distance with my friends in WV, and the one who just isn't in the inner circle of things here. And I feel so bad that even if someone invited me shopping, to a movie or over for cookies and egg nog - if I had the day off I wouldn't be good company.
I know there are worse things in the world - but this is swallowing me right now. All I want to do is curl up in a ball and cry.