Good luck mate done exactly the same as you (although not on antidepressants) after a wee cancer scare 2 years 7 months and 10 days ago….
I found it strangely easy to do, some advice to help you along your journey……download a stop smoking app, I used one called “smoke free” logo is a green heart on a white background, it’s free, Tracks the days since quitting and the amount you’ve saved I’m at £7,148.30, seek help from a smoking cessation service at the doctors if the do that in Ireland, free patches, gum, etc, and someone to talk too.
The worse thing about the whole process was the insomnia, make sure you’re oan the right strength of patches, as they keep you awake, if you can put the money away you would spend on tobacco and weed in a jar and treat yourself, so you have something to see for your efforts, I bought a rickenbacker 4003 bass costing £2,500, every time I pick it up and play it, I think “I could have burned that money” it spurs me on