He doesn't make clear whether there's any passion, intimacy and romance on these drinkies. For instance, if you're doing your stuff for 90 mins and then for two hrs later its just friendly chit chat at the bar, then take the hint, especially after numerous occasions. If you're going to the bar and you've got your arms around eachother or snuggled up and whispering sweet nothings to eachother and the occasional stolen kiss even. I can see why that would be slightly intoxicating and set the pulse racing.
But either way, just put it down as a positive experience. He met someone nice had some drinks and company and let it be... otherwise, I agree it could spell trouble esp if she has a fella and he has a wife. For example, the fella may not know about her job and being caught could let the cat out the bag (during a heated argument perhaps), the fella isn't going to be of calm and logical mind to protect the OPs privacy. Then again he may know what she does, but still wouldn't approve of her spending "civilian" time with another dude.