Here's a nice passage which shows how Jesus considered his work far more important than any other things in life, and how we can be considered his friends and relatives.

And [Jesus'] mother and his brothers came, and standing outside they sent to him and called him. And a crowd was sitting around him, and they said to him, "Your mother and your brothers are outside, seeking you." And he answered them, "Who are my mother and my brothers?" And looking about at those who sat around him, he said, "Here are my mother and my brothers! Whoever does the will of God, he is my brother and sister and mother.
Mark 3:31-35

And what exactly does God want us to do? This is answered in another passage, earlier in the Bible.

He has told you, O man, what is good; and what does the LORD require of you but to do justice, and to love kindness, and to walk humbly with your God?
Micah 6:8

We must do justice, love kindness, and walk humbly with God - then we can be Jesus' friend, and be called his brother, sister and mother.