I don't drink alcohol. I have a few reasons - I rarely enjoy the taste, it's expensive, it's not really healthy, and I don't like letting my behavior be influenced by the substances I drink - but mainly I've just never felt any kind of desire to drink.
Yet when I am out with people I don't know particularly well, they tend to be insistent that I drink alcohol with them - remarkably insistent. I've even had people get frustrated with me because I won't drink, frowning and telling me "Stop making a big deal about it, just have a drink!". I've had to make up excuses such as "I used to be an alcoholic," "I'm taking medication" or (if I am desperate) "My religion forbids me from drinking alcohol" - only then will people finally, grudgingly, leave me to my tea.
Is it wrong of me to insist not to drink alcohol, or should I, for the sake of not offending my colleagues, suck it up and drink? Is it acceptable for others to insist so strongly that I do so? Why does it even matter? I've occasionally had to tell people that I don't eat things like licorice or yam, and nobody has ever tried to insist I eat those things. I don't see the big deal. Am I violating some special social norm here?