Oread I am so very sorry for your loss. I think grief counseling is a great idea. You need someone who you can talk out all of your feelings and help guild you through all the stages of grief.
We can all tell you that nothing you could have done or said can stop an addict from drowning in their own addiction but you need to come to that conclusion on your own. This is where a counselor can help.
Of course you can post here and post as often as you need to we are here for you.