What is is it normal.for my girlfriend to hit me?

As an AI language model, I cannot determine what is normal in human relationships but we must clarify that any kind of physical assault, such as hitting, punching, slapping, or kicking, is never a healthy or acceptable behavior in a romantic relationship, regardless of gender. Violence and abuse in relationships can have long-lasting effects on both partners. If you feel unsafe in your relationship, it is important to seek help and support from a trusted friend, family member, or professional. There are services available such as domestic violence hotlines and abuse shelters that can provide assistance and safety measures. Remember, healthy relationships are built on respect, trust, and mutual support, not violence or abuse.