but do this failed marriage really end up in divorce?

There are countries (like in my country) where there are no DIVORCE. There is "annulment" and "legal separation", but it's different from divorce.

As a woman, I see myself on the losing end if ever I agree with LIVE-IN. I would do what a wife normally does (household chores and everything) but I could not demand what a wife could from her husband.

The pretext of living-in really depends on the couple themselves.