Advice please - worried about the safety of my kids

Hi - I've been incredibly stressed to the point that I have hives and my hair is falling out.

My husband has always had some really odd behaviors (as does his mom).  

He interrupts, doesn't listen, leaves his stuff everywhere (I can see exactly what he's been doing, because there's always a trail), is chronically late, is constantly teasing and harassing to the point of fury on the receiver's part, can't sit still (pens clicking, clicking the battery cover on the remotes, fiddling with whatever he can get his hands on) tries to finish my sentences because I'm taking too long (his words), drives pretty recklessly, and can literally be gone all day when he thinks he'll be gone for 5 minutes. He forgets entire conversations, and even has to call me 3 or 4 times in a row to ask me the same thing over and over.  He has angry outbursts, though they have calmed down considerably over the years.  But by outbursts, I mean things like grabbing the steering wheel from me because he wanted me to turn when I didn't, or grabbing my iPad from me, or shoving me hard because he felt I had selected the wrong checkout line and wanted me to go to a different one.  He also checks out for hours or days at a time on the Internet and/or TV.  He seems to have two modes of operation: on and off.

This was all manageable when we did not have children, and I had a career and a life outside of him.  

We now have two very young children, and besides his near inability to help me with them, my main source of anxiety is their safety.  Several times in the last month or so he has put them in danger.  He left our 18-month-old and 4-year-old outside alone, with the baby teetering at the top of cement stairwell (with a huge drop-off on two sides) leading to the basement.  DH was supposed to be outside watching them while I cooked dinner inside.  He came into the house and was hanging out when I I realized they weren't with him and asked where the kids were.  "Oh, outside.  They're fine."  I ran out and the 4-year-old was beside herself trying to keep her brother from falling.

A few weeks later, he left them alone on the front porch.  The baby fell off and hit his head.  He was okay but it could have easily ended in tragedy.  He could have easily put his eye out with the bushes or hit his head even harder.  DH brushed it off, but then later admitted he felt really bad.  I told him he absolutely cannot leave the kids unattended (he was supposed to be watching them while I went to the bathroom, and they were all inside when I left them).  Just thinking about what could have been makes me sick.  What saved my son was that he fell off sideways into a bush, and didn't tumble forward onto the concrete steps.  He scraped his temple on the way down.

He can never remember to close gates and doors.  Once when we were abroad, he left the front door of our apartment open and didn't realize until I ran out and saved our then 16-month-old daughter from falling down an elevator shaft (it was in Italy, and apparently the code there allows for kid-sized, easily accessible openings to the shaft).

When I talk to him about safety precautions with the kids, he scoffs and thinks those are all for idiots.  I ask him not to let them eat food they can choke on in the car, because he probably wouldn't notice that anything's amiss until it's too late.  Especially with the baby, who is still rear-facing.  Yet he still gives them things that are known choking hazards, like apples and popcorn, in the car.

And speaking of the car, he has no problem texting and driving, or doing just about anything on his phone, while driving, with the kids in the back.  Once he even wanted to Skype while driving!  I've begged him over and over to stop, but he doesn't.  He thinks that the rules and studies don't apply to him, that he has some special powers that allow him to do it when everyone else can't.  I'm not joking - that's what he has said.  So I'm worried every time he takes the kids with him.

He also constantly teases our daughter until she cries.  She tells me regularly that she doesn't like him and doesn't want to be around him.  I try to step in when I can, but DH gets mad at me for undermining him...but I also can't just stand by while he makes her cry for his own amusement!  I don't want her feeling like she deserves that sort of thing, so I tell him to knock it off in front of her.  

She also gets frustrated with him because when she's trying to share something with him, he turns it around and makes it into some self-amusement thing that's only fun for him.  Like if she's trying to sing him a new song she learned, he interrupts her and starts singing the wrong words on purpose, over and over, until she cries.

He also recently got too rough with my daughter.  She was misbehaving at bedtime and it pressed his buttons.  He had asked her to do something, and she actually did it, but he was so far gone that he didn't notice.  He picked her up by one arm, carried her to her bed, and flung her down.  She started wailing.  He said it was my fault for giving her cues to cry, and that she was fine.  I told him to apologize to her, but he wouldn't.  I made him leave and got her calmed down.  Once she was asleep I confronted him.  He kept brushing it off until I yelled at him and told him that he was ruining his relationship with her, and that his behavior was NOT OKAY.  He said sorry, and I said don't apologize to me, make it right with our daughter.

And this is way less grave than the kids, but last week he gave my cat away on the Internet.  He has allergies.  Five years ago we had discussed finding the cat a new home, but he did nothing (but kept complaining).  One day, five years later, he decided to take action and told me after the fact.  I am so sad.  I miss her terribly.  She was a real comfort to me.  He says I should be sad for him and his allergies, and not be choosing the cat over his health.  I got to meet the woman who took her, and she's wonderful.  And maybe in the end, it's for the better.  But I'm still really sad. 

I don't know what to do.  We have no diagnosis - it is just my hunch that this is ADHD.  I want to get help, but don't know where to start.  We've already been to therapy before, but it was a good 8 or 9 years ago, and ADHD was never brought up (or at least not that I remember).  I want to talk to him about the possibility of ADHD.  I just don't think this is normal behavior, right?  Right???

It all started to unravel a few months ago when I was rear-ended on the highway and injured.  DH just checked out and left me to flounder with the kids.  I'm doing much better, but the thought that everything rests on me with the kids is scary.

He's not a bad person.  He's really smart, and charming and funny.  And in a lot of ways he's a really good dad, and I know he loves the kids.  But I'm so tired.  The only time he seems self aware is when he's had to spend time with his mom and her behaviors (same as his) drive him insane.


How should I approach him?  Should I just start therapy by myself anyway?


Thanks in advance for listening.