People who are prone to addictions of any kind, what keeps you going knowing there are grave consequences in what you do?

I used to be very addicted to Monster. I have a bad heart now from all those years, so I don't drink it anymore for the most part. I do sometimes if I didn't get any sleep, but it really hurts my heart. And Idk why I do it. Maybe just to get through my shift, Idk.