I got dumped by the girl of my dreams in April. I completely scared her away. I was moving way too fast and she left. I became totally obsessed with her. Now the obsession is with me. I think about how I screwed it up and I torture my myself every day. I'm having such a hard time with the regret and it's put me into a bad depression. I have been seeing a therapist since May and it seems like it might be helping a little. But I still have a hard time dealing with what I did. I just can't get the "WHAT COULD HAVE BEEN" out of my mind. I still dream about her all of the time. I think about her all day.
It's starting to really scare me. I know it sounds silly, but I feel like I lost my only true love and I will never love like that again. I have dated several women in the past and never have I felt like this after a breakup. I just feel like my ship came in and I sank it. Now I have left myself to tread water. Will this ever go away?

Yes, it will. You need to talk with Sneezy (ISneezeFunny). He will give you the straight dope on how to get past this. He did it with style and grace and even some wit.

Here's the thread (I told him there is a publishable book in there somewhere):

https://www.askmehelpdesk.com/relationships/am-doing-nc-what-about-her-161688.html?highlight=isneezefunny

Continue with your therapy.

"WHAT COULD HAVE BEEN" is a fantasy... don't live in fantasy, struggle to live in the real world, with real people communicating with each other.

I know it isn't easy once you fixate on your fantasy, but for your own happiness and peace of mind, you have to fight the fantasizing.

Very best wishes to you, :)