Separation Anxiety or Something Deeper?

Today I was reminded of the fragility of my children's hearts.  Every Thursday we have our preschool group.  This is a group of five families who are homeschooling.  We get together each week for music, discovery, art and playtime.  The boys love going to school.  They love to play with their friends.  Sometimes they have a difficult time with the other activities, but they have come a long way since we started this group almost two years ago.  However, one thing remains the same with my boys.  They do not like when I am not with them.  They always whine a little when it is my turn to stay with the babies.  However, I am still in the house, just in another room.  They will often check on me and then will go back with their group when I send them back. 
Today was different.  Today was a beautiful day, and my turn to help with the babies.  So, the other mom and I decided to take the little ones in the strollers for a walk.  As soon as Jachin realized that I would be leaving the house, he had a panicked expression on his face.  He grabbed my legs, my arms, my hair, anything he could get a hold of and would not let go.  He begged me to stay with him.  He cried.  Another mom, a good family friend and someone Jachin knows and trusts, held him.  He punched and tried to break free, as he was reaching for me. 
I went for a walk.....and I regret it now.  I felt badly at the time, but I thought that perhaps it would be good for him to see me go and come back.  Perhaps he will see that (Lord willing) I will always come back to him.
Maybe some would think that it was best for him to do without me, even though he felt like he couldn't. However, I think that I was wrong.  When I got back from the walk, Jachin looked at me shyly and came over.  He did not extend his arms to me.  He just stood in front of me, waiting...  What was he waiting for?  I am writing through my tears right now, because I know that he was waiting to see if I would come to him, if I would love him and make him feel important again.  I let him down.  I left him when he did everything to show me that he needed me to stay.  I don't know why he needed me.  Other kids his age do fine when their moms leave for 1/2 hour.  But Jachin did not have all the privileges that other kids have had.  For over two years, he didn't have the security of a mom and dad.  He had NO ONE!  No one came for him.  No one treasured him.  No one made him feel like he was the most important person in the world.  For two years, my little boy had to do without a mommy; he had to do without..without..without...always yearning for love and never being fulfilled.  "Well", some might say, "He's been with you for almost 3 years now; he should feel secure and loved; he doesn't remember those two years before coming to you."  Ah..perhaps a child's mind cannot remember the neglect, the pain, the fear, but I dare say that a child's heart does not forget.  I will not make the mistake of leaving him again when he is begging me to wrap my arms around him and make him feel like he is the most important person to me.   My little boys deserve to feel loved at every moment!  I'm sorry, my sweet Jachin.  I love you more than I could express!  I am proud of you.  You and Josiah are my precious gifts from God!