What do you do with your emotions when you start feeling them?

I’ve learned from the addictions community that we use whatever we are addicted to in order to mask emotions that are painful to feel. If you stop using, you go into withdrawal, and you start feeling all those emotions, which can be extremely painful.

Anyway, it seems like most people think it’s better to feel the feelings than to mask them with some substance or activity that raises your dopamine levels. But what do you do when you start feeling that pain, wherever it comes from? What do you do? How do you deal with it? What is the advantage of feeling pain? Especially if the last time you felt that pain, it nearly killed you?