Hi Newlywed41 and WELCOME to SR. This is an awesome place to find support and sometimes some off-color humour. I'm glad you found us.
I'm sorry you're in such a rotten situation. For the record and just in case you don't know them already, here are the 3 C's of addiction:
You didn't CAUSE it
You can't CURE it
You can't CONTROL it
There really is nothing you can do or say (or NOT do or NOT say) to change your AH (alcoholic husband)'s drinking. You simply do not have the power to do that. Only HE can decide when and if he's had enough. In the meantime, you can focus on the only person you do have power over: you.
Ask yourself what you are willing to live with in this marriage. Can you handle the lack of honesty? Can you handle the danger your AH is putting himself in by driving drunk? What if he injures/kills someone while doing so?
Now is the time to find yourself an Al-Anon meeting in your area and attend. There really is nothing like having the support of people who've been exactly where you are right now.
Now is also the time to think real hard about your boundaries and enforce them. As you suspect, empty threats don't do jack because they convey the message that you won't ever follow through. In a sense, you are "training" him to continue to treat you the way he does.
I know that right now you're riding on this rollercoaster of ups and downs, which fluctuate according to his drinking. Do you really want to live like this? You know you do have the option of getting off the ride and saying "enough"...
Finally, I wanted to speak to your statement about not being able to confide in your family about your AH...It simply isn't your responsibility to protect HIS reputation with your family. Yes, they may be disappointed and seek to protect you, however, you aren't the one who created this situation, HE is, by continuing to choose to drink. Don't let shame or guilt isolate you; this disease thrives in the dark. Reach out and get the support you need to get through this...if it isn't through your family, perhaps through your friends, or through a counsellor. You may also be surprised to find out that your family already knew he was an alcoholic...
*hugs*
Please keep posting and reading as much as you like. I highly recommend reading some of the Classic Reading stickies at the top of the page.