Staying sober never is easy. You must persistently fight against what you know isn't good for you even if you body craves for it. Most former addicts who don't change their habits after quitting, hang out with friends who still do drugs and visit places they associate with their previous drug use, end up relapsing. The easy way to avoid all that is to learn new habits. Make new friends with different people who'll be a good influence. Stay away from everything that reminds you of drug use and you'll most likely stay sober for as long as you stick with the new habits you learn.