How does the chaser effect happen?

As far as I am aware it is down to deltafosb causing people to take full advantage of it when they get it?

The strange thing is I go without P for weeks or a month and have no interest in it. But then when I do relapse on it I go in to these binges that last a day and it's as if in that day I can't get enough of it. But then after that day I go back to not caring about it.

I never relapse once quickly and then stop. I always end up binging. Like I said when I relapse once it's as if I can't get enough of it. But then after I do stop I go back to not caring about it.