If you want to know God’s will you should pray and read your bible. If it a hard question ask other people to pray for you.
I think maybe you are giving too much power to a picture you saw … or applying the message in the wrong context.
As far a blocking on facebook, why are you blocking them? Are you doing it to hurt them? or are you doing it to protect yourself?
If you find you want to be hurtful to another person you should look at why you feel that way.
Some people have no sense of boundaries, and I think it is a good idea to block them. I had a boss once who I blocked from my facebook page. There were two reasons, one was he did not have very good respect for boundaries. Another was because I sometimes complained about work and about him on my facebook page. If I wanted to complain about my boss there were proper channels at work for me to use. If I needed to vent and talk to my friends, he did not need to see it.
I’ve certainly known people who facebook kept suggesting as friends, and I knew they did not want to talk about to me about their life. If I had friended them … it would have been 100% o.k. for them to block me.
I think in my life I have seen three case where God really wanted to put one person in another person’s life. God had no problem getting around circumstances and stubbornness … I think what is more realistic almost all the time is there are people in our lives and we can choose to learn ways to make God’s love evident in their lives … or we can choose to do our own thing. But mostly what maters is not who is in our life, but how we choose to treat them … to build them up in the Lord or tear them down.