How long does this last?

Tonight I looked at a picture of my mother and my Sarah and it hurt.  Deeply hurt.  I honestly thought I had moved past some of the pain, but I am now realizing that grief is a cycle.  A process of ups and downs.  A Ferris wheel of highs and lows.  Just when you think you are doing better, when you are able to go through your entire day without crying, it hits.  The grief.  The pain.  The sadness.  The tears.

 I wonder how long it will take for me to work through this process.  Then I wonder, if I finally feel that I have worked through it will that mean that I don't think of my mother that often?  Will I go about my daily life without remembering her?  Will I become so far removed from her and her death that it will feel like it happened in another lifetime?  If I live to be 63, then I will have had my mother for exactly half of my life.  I will have lived half of my life with her and half of my life without her.  That seems odd to me, to be able to live half of my life without my mother.  That doesn't make sense to me and as I have said so many times before, it just doesn't seem fair. 

Today I read some of book three of Journeying Through Grief, and I found this poem written by C.S Lewis when he lost his wife. I think it speaks to exactly how I am feeling lately. 

No one knows
the tears still inside me.

People think it's all past.
They think I'm all better.

Every once in a while
I think, I hope, I pray
that things will be better too.

But then I remember.
And the pain floods back,
and the bottom falls out,
and I fall and I fall.

And I know once again
that things aren't all better.
My loved one is gone,
and I cry alone.

How much longer, God?
How long does this last?

That my friends, is my question tonight.  How long does this last?