Need advice about 4 yo DD

PoundCake

She is asking a lot lately for her dad.  She'll say "I miss my daddy." And last night she told me that I should "Go to the doctors and let daddy come home."

When he first left the house, we said daddy was sick and had to get better before he came home.  That was last April.  I thought he would try to get help for his addiction.

I tell her that daddy loves her and misses her, that sometimes mommy and daddies can't live together because its better for us to be apart but we do love you, etc.  It doesn't help he doesn't call and hardly sees the kids.

She gets so upset and I just want to scream.  Inside I can hear myself screaming daddy is a jerk and I hate him.  But I can't do that.  I just don't know how to help her when she gets so upset and starts crying.

I say the same thing over and over and tell her he loves her.  Any other ideas?