Just bouncing.
According to ER she's not sure, but he's been driving truck.
Drinking as a truck driver is a big big big big deal. They can and DO random tests to confirm sobriety. It's one of the only well enforced rules in the industry.
Once you get a CDL you have a whole different set of rules to abide by. You can not have had anything to drink in 4-8 hours prior to dispatch, and you have to be under .00 at all times, although some claim you can be up to .04 in a private vehicle. Still, even one drink will put you over.
It's not just a company policy thing either, CDL is state issued and the state has a ZERO tolerance policy. You have to stop at weigh stations and talk to state employees, and drop off goods and talk to people there. You WILL get reported if you so much as smell of booze. It's considered a privilege to drive truck, not a right. Your books have to be accurate and updated at all time, which doesn't mesh too well with drinking.
IOW, if he had a drinking problem he was capable of turning it off for decent lengths of time. Either that or he has some drinking episodes rather than long term problem or has sobered up.