Not sleeping well

I don't sleep very well and have disturbing thoughts that wake me often.  The state that I am in is extremely depressed and I feel so much blame.  I wasn't the most wonderful mom that I had envisioned and was told in the past by my children.  I keep going over the ugly things I could have done differently.  The death of our oldest I now blame myself for.  This adds to the guilt and I try to let it go, but it is like tar.  Sticking and sucking me into the muck.  I am hopeful that the support here will help me and give me the strength that I need to go on.  I have a husband to think of and want to be the best for him.  Right now we are both in the struggle to regain some sanity.