I think there's different types of work/life balance. Temporal, spatial, social, etc. Some people strive to keep their work and personal locations explicitly separate. Others set timers and hard boundaries as to exactly when they're "working." Others avoid mixing their personal social lives with work social lives.

The person you're replying to is pretty similar to me, where I use the fact that I have a physical office as my work/life boundary. But I also don't shy away from having a social life when I'm within the work side of the boundary, and another social life when I'm on the outside. If you spend 1/3 of your life on the inside, you can have fun there without contradicting your personal work/life balance.