If a person injests enough of any substance for a long time, and if that person has negative physical and emotional symptoms when they stop injesting that substance, then the substance is addicting. I have known people who drank a lot of diet Coke throughout the day (contains caffeine) and then had the same headaches, jitters, and nausea, etc. when they stopped drinking it - the same symptoms that happen when people go through withdrawal when they stop drinking coffee.
I've noticed that recently when I visit the Coffee Forum and read all of the posts about coffee, I suddenly want to have a cup of coffee. If I walk away from the computer and go do something else, the thought usually goes away. I doubt that reading and discussing something can make you addicted. If you're already addicted, reading and discussing it will make the cravings come real fast.
Rose