Thanks everyone for your insightful responses. I find it oddly comforting that my wife is wrestling and struggling with these challenges, as I suspected, but clearly at odds with all her assertions to the contrary. Not because I like that fact, far from it, just because it's really helpful for me in trying as best I can to understand and deal with it.
Last night she came home and spent the night drinking from her usual water bottle. It was only later at bed time that I noticed she had stashed an empty wine bottle on a shelf (of all the places to hide it this was the most stupid) and that she had poured the bottle into her water bottle to drink, as if I wouldn't notice! I guess it's that warped sense of reality and belief that plainly irrational behavior is justified and excused as reasonable or normal that sets alcoholics apart. I see also what many say about wanting to stop. I guess anyone who knew they were going to get drunk every night would just shop in bulk and be done with it, but with her it's a trip to our local shop (we live in the countryside so there is only one) pretty much every night. Even when she does a 'big shop' at larger shop in town she'll only buy 2-3 bottles, and they'll go that night. Otherwise, come 17:00, she's making excuses to go to the shop (last night wee needed bread apparently) and then she's off to her study alone for 90 mins.
I appreciate everyone was different as a drunk, but there are plenty of themes emerging, not least plenty I see in my wife.
Sge also sleeps appallingly. If drunk she'll pass out snoring if she's lucky enough to have got to bed in time, but often wake and be restless and up by 05:00. I assume this is the effects of alcohol wearing off? I guess the next step for her (she's not there yet thankfully) is daytime drinking to take the edge off?
Thanks everyone, I really welcome your honesty and your candid thoughts on whatever dark places you've been, really helpful.