The alcohol used in chemistry labs is indeed a poison, but it’s completely different from the alcohol that is found in a yummy glass of wine, an ice-cold beer, or a refreshing gin and tonic.
There was a recent thread on this forum about how to deal with people who are judgmental of others about how they manage and treat their diabetes. That might be a good thread for you to read through. I believe the subject was, “How to deal with people who think they know it all about diabetes.”