Choices made can't be undone

I've made my decision. I know what I had wasn't healthy and wasn't good for myself or the kiddo... but then, why does it hurt so much? If I made the right choices, shouldn't I be happier about it? Or at least not hurting so much?
Being happy isn't about having what you want, its wanting what you have... but stupid as it is, I still kinda want what I had. My heart can't let go of the love there was. I know it takes time, and given enough of it, I will be ok.
Will I always wonder what if...? Will I regret turning away from someone who claimed to love me more than any one else ever would? Was I right that the level of abuse would have escalated? Was I wrong to deny my daughter a more stable life with a father figure who cared about her?  When will I get my head on straight and just... forget???

I don't understand.

I lie in bed at night, a million thoughts flit through my head like fireflies... Here, and then so quickly gone. Why are you the one filling up my thoughts? Its over, you're gone... never to be heard from again.  I should be grateful, relieved. Instead, I'm nostalgic and missing you.  Was it ever that great, that I should mourn and long for you this much? Or is it just my silly, sentimental heart- playing tricks on me? I knew it wasn't going to end well between us, I hoped otherwise... but I was never foolish enough to believe it would last. As I'm plagued with anoher sleepless hour, I'll try to find some peace... after all, happiness lies not in having what you want- but wanting what you have.