Hurting...can't let go..

I hate myself for this..I miss him or who he once was 4 yrs ago. I hate that I'm only 25 n takin so long to get over one stupid abusive asshole. He treated me so horribly n yet I still cannot understand why. Why Is this process taking so long?? And why am I not turned off by the physical abuse? The verbal which hurt more than anything? He texted me saying some horrible things b4 I went NC for the last time y do I give a shit what he thinks of me? Why do I wish he was different when I know he will never change? Why am wondering who he is seeing now? The other day a friend of his posted a pic of him n my heart sank. I still love him so much!! I feel like I've already given him so much of me I know this takes time but it still hurts..why do they do this to us? And we are the ones left hangin on for dear life?? I'm constantly thinking of him n someone else I know it's stupid but I can't help where my mind wanders... I wish I never met him. I just want this to be over I'm finding it hard to even meet guys or be myself.. I don't know what he did to me:-(