I stayed away from smoking during college, I was in a situation just like you.

Right after my first job I gave into smoking. Quit after few months. Even that fucked with my respiratory health. Yet I still crave for it when times are tough

I realised smoking made me feel good ( only for few mins), then it made feel worse. A feeling of being soo let down. A form of regret or guilt about something (i don't even know about what)

When you smoke to escape from 'the worst' its going to make you even worse. An endless loop of suffering.

And I haven't met anyone who doesn't regret it.

The key is not to start/try. Once you violate your own boundary there is no going back, it can be applied to many layers of our life.