Backstory:
As long as I could remember I have always became a completely different person 2 days-a months after I drink, to the point where neither of these things are even remotely fun anymore. The simple answer is to stop drinking, I understand, but it doesn't answer why it happens. 

Connections:
I've always thought that potentially it could be connected with a big swing in serotonin as I am super happy and stress free when drunk. So following it seems like a whole reset.

Symptoms:
In the following weeks typically it can only take one negative thing to send me into a downward negative thought spiral. I start to lose all hope, everyday things become much harder. The BIGGEST issue is my mania, I begin to feel strongly on many negative things I do not want to think about, whether it comes down to evil thoughts, thoughts of cheating, you name it I start to think it excessively.I become incredibly depressed and there feels like a physical weight in the front of my head. Typically, it feels like there's no way to get out of these funks without just letting it pass naturally. And then all of these cease. 

Now you are probably thinking that this may all be in my head, but with the 30 consecutive times (ages 16-24)  it's happened I thing it's beyond chance. This doesn't discount the effect my mentality may have on it, but I don't believe it to be the root cause.