It's been 5 years or so since my last cigarette, and I still desperately crave one when I've had a beer or five, especially when there are other people smoking nearby (like at a pub).

For these first few months, try to socialise in places where booze and other smokers aren't going to mix - like getting blasted at your house instead of your local. Ignoring the cravings does get easier, but for the first while being out of the way of temptation definitely makes things easier.

(Also replacing tobacco with weed is a bad idea, since you'll just end up smoking as much weed as you used to smoke tobacco in order to stave off the cravings then you'll be drooling on your sofa all day with a small packet of wotsits and a large box of shame and oh the humanity)