This is a combination of "to blow my top" and "to lose my shit". The typical usage is in text messages between friends who are angry with their spouses and need to vent.
"My damn wife asked me to return something to the store, but she hasn't got off the phone to tell me what it is. I am about toblose it with her."
church hurt is where you experience a degree of distance, pain, or judgement from your church community. Essentially, you are just unable to “find your place”. This is prevalent in the Christian community, but can be extended to other religions.
Now that I am an adult I am beginning to heal from the church hurt that was inflicted on me as a child.