In this matter you should talk to your girlfriend and make her believe that her insecurities are worthless and she should not feel this way. Talk to her openly and understand why she is behaving this way. After the discussion, if you feel that her points are valid and you can work on it then go ahead and if you think that she is only messing around then the rest of the choice is yours what you want to do ahead. Do not give space for toxicity in the relationship, communicate for better understanding instead of making scenarios.