Hi Emerdale, as you are diet only an occasional drink should not present any problems and as daisy has said red wine is a good choice if taken in moderation.
Alcohol is more dangerous for diabetics who use insulin or other hypo inducing meds as the liver deals with removing toxins from the blood and alcohol is a toxin While the liver is dealing with the alcohol it does not regulate the release of glucose so if a diabetics blood glucose drops low then they are more at risk of a serious hypo as their liver will not be able to release glucose to raise their blood glucose levels.
I believe that the liver can clean in the region of one unit of alcohol per hour so it is easy to see how long it will be out of action for if you are drinking all night
To help stabilise blood glucose levels overnight after a night out it is a good idea to eat a carby snack before bed to help keep levels up till morning.
T2's on metformin or diet only are much less likely to suffer a hypoglycaemic event but it is worth bearing the above in mind before embarking on a night out with the boys, or girls
A few bar snacks, crisps etc will help to keep levels up, I was told when I was on insulin that a slice of pizza on the way home was a good practice due to its slow release of carbs.
Thankfully I can no longer drink like I used to as I cant handle the hangovers any more but I do enjoy a glass or two of red wine of an evening or a glass of Cobra lager if I eat a curry.