Why are sober relationships so difficult?

In my current relationship, I don't even know what to call it.  He broke up with me because he is miserable.  He is on house arrest in my home, and that saying you always hurt the one's you love, seems to be holding true.When he's happy, I remember why I fell in love.  But he's been swearing he is gonna move out for a while now, and it's become the whole I'll believe it when I see it.   I don't want him to leave, but I am past begging him to stay.  

When we both were using, our relationship was alright, but drugs hid us from ourselves, and that 2 years, neither of us grew.  Now, we are both clean but instead of taking life by the horns, he seems stuck.  I started my writing, and he has admitted that it sometimes bothers him.  He's also admitted that he's jealous, because his life long dream to be a signed dj, seems like a pipe dream.  

I have found myself having to hold my ground, when he is whining, "I want crack."  I say no, because I want to move forward in my life.  Yes smoking some crack would be fun, but I do not want to even go down that path.  

I was told at my first NA meeting, "Sobriety will bring your wildest dreams."  So far it has.  I don't think if I was clean, I would have never had the drive to finish what I started.

I think what makes sober relationships so hard is when one addict grows, and the other addict is stuck holding on to bad feeling and can't grow.