Ex-gf refuses to move out

again, if the owner of the rental is informed than yes OP can be kicked out but that is a risk he should taken for violating the rules. But it is better than a issue that ex girl friend is getting crazy and torn down the place or make but drama.

Again I never heard about living together is EQUAL to marriage.
So it means that I can marry anyone without doing the formal process just to live with someone.
I keep that in mind than.

I have looked up similar cases in a local question forum, and there seem to be many cases like yours. Lawyers answering the questions do mention going to court, but for cost and time reasons, they suggest paying off a reasonable amount to get them to move out.

I tend to agree. After you get her to move out, you could explain the situation to the landlord (apologize if the maximum occupancy was just one person), and get the lock changed.