She may feel guilty about it and hide her phone from you. She may spend more time with her phone. This secret behavior may be a problem for relationship.
Sex is important part of relationship, we all know it If she avoid sex and try to be away from you that might be a sign of negative think about your relationship.
Every woman wants to change their look while they are starting new think.
Women like to share their feelings with man; but if she hide something and not open to you that is a problem.
This may indicate that she feels you inadequate.
Tags: 5 signs that she is cheating on you,signs that she is cheating on you,signs that your girlfriend is cheating on you