>How do I learn to deal with this, as short of finding a new job (where there very well may be another person with the same personality type), I'm not going to be able to simply avoid it all the time.

You don't avoid it, you correct it.  "I'm sorry, that was inappropriate, please do not comment on what I choose to drink/eat/do."

That's all you need to say.  Don't be nasty, don't be aggressive, just stop the behavior.