Both.
All drugs impact the user based on "set and setting." Your mindset, plus your physical and emotional surroundings, determine the experience.
Having a bourbon alone after a long day is a great way to relax, but it's totally different than having a drink with friends, despite alcohol's involvement in both. The same holds true for coffee. A morning cup on the run affects you differently than getting a coffee with friends.
Smoking alone makes for a peaceful and pensive experience, smoking while driving cuts down on boredom, and smoking with friends leads to deep, meaningful, or fun-but-trivial discussions. Each has its place.
The Lord of the Rings was a fantastical accounting of Tolkien's experience in WWI, in which he and his compatriots traveled the countryside, smoking and bullshitting wherever they stopped. Tolkien smoked alone too, but it's his tale of companionship that constantly brings new smokers into the fold.