Hey...I'm sorry for what you are going through. Your husband is "acting out" and you are his scapegoat. Your sons are taking advantage of the imbalance of power in your home right now.
As long as you walk on egg shells, He will continue to lay the eggs...Nip it in the bud. Tell him he has to get therapy to deal with his grief. He has lost his dad, which will not change. However, he will lose his family if he doesn't get help. As for your boys, I totally believe in old school "take away their privileges, whether physical or technological". Take it all away to show them you're not playing.
TAKE BACK YOUR POWER before you are lost in HIS.
Hugs~~Dixie