My girlfriend went to the hotel with someone else. How should I face it?

You can't stand this kind of thing. If you don't have prestige, others will. It depends on your acceptance. But she is still honest and will tell you when she comes back. If she refuses to admit her death, you have no proof, so I can see that she still loves you. I don't think she will tell you if she cheats again. I think you are in pain. Think about it. It will be very tiring to live with such a knot all your life.