Hello, I'd like to help you with your question.
It is very hard to face the pain of a betrayal in your relationship. It alters what you believed about your relationship at a very basic level. It takes from you that love and connection you felt you had and replaces it with pain and anger. What your girlfriend did
undermined your ability to trust her. And when you give yourself totally to a relationship, you want to be able to trust that person. If that trust is taken away, then it can be hard to rebuild.
There are two parts to the situation. One, is what your girlfriend did and whether or not she is sorry. If she is sorry and does make amends, then your relationship has a chance. In order to do that, your girlfriend must take responsibility and own up to her behavior. It sounds like she has done that, which is a good sign. Now she must prove that she will continue to do what she said she would do so you can rebuild your trust.
The other part of this is your feelings. Anger often covers pain. It is a normal reaction to the betrayal you suffered. You are hurt, probably very deeply. And you may not know where you stand in the relationship anymore because it has all been altered by your girlfriend's cheating. Knowing if you should continue the relationship is a difficult decision, especially when you are in pain.
What is helpful is to give this time. You are just starting to deal with your feelings and your girlfriend has not had time to make this up to you by proving she can be trusted. Allow her time to make amends. She should be allowing you to ask any questions you want of her. She also needs to be transparent with her activities, even if she doesn't want to. You need the reassurance that you know she is not cheating again. This does not mean you control her, but rather that you have the right to know where she is and who she is with.
Also, talk about how you feel. Be sure you don't stay just with your anger but also allow yourself to feel hurt too. This is painful and acknowledging that can make a big difference. If you have family and friends to talk with, that is good. If not, consider therapy. Your relationship may be new, but it is worth giving it the chance it deserves.
I hope this has helped you,