Angry outbursts turn physical

My husband and I are both likely add, as one psychologist and one psychiatrist have suggested we probably are, but have never been formally diagnosed.  We have 2 boys, one just turned 8, the other is 2.  The 8 year old is adhd.  My husband has always been frequently angry.  His favorite shirt (which I got him) says "I'd rather be complaining."  He is convinced that he knows best about a great many things, and this attitude often seems to be the source of his anger and frustration with life in general.  In the nearly 14 years that we've been together, I doubt a day has gone by without at least one angry outburst.  We've been seeing a marital counselor for several years.  My husband has found parenting our 8 year old son to be extremely challenging (honestly, so do I).  I've been working very hard for the past several months to calm down when I begin feeling angry at my son and parenting from a better place emotionally.  For this same period of time, I've been trying to give one-word signals or nonverbal signals to my husband for him to calm down.  I've done my best to encourage him to listen to some parenting cd's I purchased or shared books I've read, etc, etc, but he's made it clear he is not interested in these sorts of things.  I decided giving him signals (such that our kids might not notice) was the one thing I could do to help him.  I worked the strategy out with him beforehand.  It's hard to tell if it's made any difference.  Perhaps. 

About one week ago, my husband had a violent outburst.  He and the boys had just returned home from an errand.  Both boys come flying through the door with my husband close behind.  My older son throws himself at me and my husband is growling angrily at my son.  He grabs my son's shirt and yanks him hard toward the garage door, knocking over our 2 year old in the process.  My older son collapses on the floor in pain and fear, and my 2 year old is on his butt crying.  At this point, I'm in-between my husband and the kids, telling him to get out of the house.  He refuses and tells me to get out of the way.  When I refuse, he pushes me and I push back with all my strength and maintain the buffer between me and my kids.  If he had used all his strength, there's no way I could have held my ground, so I do know he held back some.  I told him I would call the police if he didn't go away.  I almost whispered it, I could barely believe I was saying it.  He and I stood there looking at each other and he eventually walked off and I didn't see him again for several hours. 

Since then, he's been apologetic, and in the past few days, he acts as if nothing happened.  With physical violence in my childhood, I am especially sensitive to it, but I know even someone without that history would find this beyond anything normal.  I've told him that I wanted to hear from him how he was going to move forward and what changes he was going to make.  As of today, he's had nothing to say.

I've put a call in to our marital counselor, asking for the first possible appointment.  I am struggling to define what it is that I'm feeling and how I want to move forward from here.  I was hoping some folks on this list might be able to help me think about this from perhaps a perspective I haven't used yet.  Right now, I don't have a clue what would be best for me and the kids.