I'm really sorry to hear that Dodie, best wishes to you in this rough time.
Whilst in my late teens I entered into a decade of addiction, I had issues with speed, lsd, alcohol, sniffing various chemicals & mushrooms are just the tip of the iceberg that nearly sunk me. Giving those up was hard, it took me almost killing myself by falling asleep & almost into a large piece of moving machinery due to being awake for days on end due to speed to make me give up.
Givimg those up was a walk in the park compared to nicotine