You did not at all let Oscar down in any way, OM! He is still in a home where he is loved and well cared for which is all a dog could wish for. He is probably missing you and the kids, but he'll adapt.
I hope things start looking up for you very soon. Good on you for asking help. And someone taught me the term 'to pay it forward' recently. I love that! There will be times when you are in a position when you can help someone in need out too and will earn yourself some karma points. Hang in there.