Mine has always had no problem lying. He says it's such a big part of his job that he doesn't think twice about it. I hear him lie to his customers(trying to cover up for mistakes his company made so I guess the whole management team backs him up on these), he lies to his boss, he lies to me about the stupidest stuff. Like yesterday when he said, "Yeah, I went back to my hotel and made a bunch of calls." Umm, I paid the cell phone bill this AM and he didn't have any phone calls made. It's just silly but very natural to him.
His mother said he was a klepto when he was a child. He would steal TV Guides, gum,and candy from stores and she would march him back in and make him confess and humiliate him but he kept doing it and kept lying about it. I honestly believe it's just in his nature and I have no idea if it's related to the alcoholism.