I used to be the young people who love the work and made the work dominate my work life balance. My reason was quite simple: I felt this is the first time I have my ability validated, furthermore I was constantly surpassing my own expectations, I don't want it to stop. So in other words I don't belong to the group that are pretending to love work.

For a long time I automatically think others must felt the same way. On the other hand I think it's not efficient nor effective to pretend that you love your work: you are evaluated based on your performance/competence anyway, although in work environment we like to call it your "enthusiasm", the pretending only works in certain working environment with a certain culture, theoretically.