I’m unable to understand what’s happening to me.

I don't know what the fuck is happening to me. It feels like I have lost my sense of self. I wake up every day and I check my phone, and I see if there are any messages from her, if there's any notification that has her name. If she wants to say something to me, or she wants to talk to me. Then by the middle of the day, I try to get by through the day by chasing some cheap dopamine. Then I continue with that cycle where I just chase some cheap dopamine, or think about her, or the things that went wrong, or how I need to move on, or she's never coming back. By evening, I try to chase some other cheap dopamine by either talking to friends or telling them what I thought about today. And then completely relying on them trying to make me feel better. And then I think about her more. And after that, I think about what she's doing, how she's doing, what she might be thinking, what she might be doing, who she might be talking to, how is she coping with it. Then I try to forget about it all, and then I try to calm myself. I get an ounce of motivation in the whole day where it is just about that I got to buck up and just live through the pain and still try to do something. But in the end, I know, in the end of the day when I am about to go to sleep, I know how hard today has been, and how hard tomorrow is going to be without her as well. And in all of this, and in months and months of this, I've just forgotten who I was and what I wanted other than her in life. And I don't know how to get myself back. And I don't know how to get her back. I don't know how to be happy anymore.