This dream contains intense imagery and emotions, which can reflect various aspects of your subconscious mind. Here are some possible interpretations:

1. Conflict and Fear: The bar fight and violence may symbolize inner turmoil or conflict in your life. It could indicate feelings of being overwhelmed by external chaos or stress, possibly related to relationships or situations where you feel unsafe or threatened.
2. Protection and Loyalty: Your instinct to protect your childhood friend suggests a strong sense of loyalty and responsibility. This could reflect your desire to safeguard those you care about from harm, or it may indicate that you feel a need to defend your own vulnerabilities in waking life.
3. Transformation and Control: The act of cutting the attacker could symbolize a transformation in which you take control over a situation that feels threatening. It may reflect your desire to assert yourself or overcome obstacles that are impacting your life or your friend's life.
4. Bleeding and Healing: Your friend's injury and the need to drag her away may suggest feelings of helplessness in a situation where you want to provide support but fear you can't help completely. This could also represent concerns you have about someone close to you who may be going through a difficult time.
5. Escaping Danger: Locking the door symbolizes a desire for security and safety. It may indicate your wish to create boundaries in your life to protect yourself and those you care about from negativity or danger.

Overall, this dream could be prompting you to reflect on your relationships, your feelings of safety, and your responses to conflict in your waking life. Consider what situations or emotions might be manifesting as this dream and how you can address them in a constructive way.