"anyone who does God's will, are my brothers sisters and mother"
How often do we treat each other as family? Really, how often? At best from what I see of most followers of Jesus we treat each other as distant cousins, at worst as aquaintences! We are mostly civil, polite and dont fight with one another. But hardly family as close as brothers and sisters!
I have 2 brothers and 2 sisters, we fought often when we lived in the same house. So much so that my father when asked what he wanted as a present for birthdays etc would respond "peace and quiet". We always thought he was joking but now as a father I am begining to understand.
However if anyone attacked one of us from outside our group we would always be the first to defend each other. If one of us was in need all the others would help, without asking? Support was a constant. Does that sound like your experience of "church"?