Can you have a traumatic episode 7 hours after mixing adavan with alcohol? "episode" being reliving a painful memoery of a prior event.

Perhaps. Both alcohol and Ativan (lorazepam) are sedatives; withdrawal from either one of the medications (or both together) can cause a hypervigilant/overstimulated/anxious state similar to stimulants.
Not a good idea. First and foremost: don't mix Ativan (lorazepam) and alcohol. They don't play well together. Their similarities mean one can 'overdose' more easily and the results can be very dangerous. If you take ativan, (lorazepam) don't drink, and vice versa. What you describe may be a flashback or a form of dissociation which is much more likely to occur in individuals who are intoxicated or taking benzodiazepines.