You're in the right spot and you're doing the right thing. Quitting is a talking sport, in my opnion. I think the thing that strengthened my quit the most (aside from posting roll) was living on this site and reading all I could. These were real quitters. I could feel people quitting with me...going through the same shit...or having recently passed through the same crap I was going through.
Owning your own business...many people think you're at the top. But really the pyramid is upside down, right? Everybody is depending on you. And when there is nowhere else for anyone to go for an answer, it sure doesn't feel like you're on top. I know the feeling well.
Never let the Nic Bitch convince you that killing yourself is a good alternative to making a stressful decision. And, don't snap at your E'ees. Believe it or not, they admire you having the strength to quit. Let them know what you're doing. Don't ask for favors or leniency...they didn't turn you into an addict, you did that yourself. And they don't have to support you now...that's our job. Don't rip their heads off, count to 10 or something, take a walk, whatever. Just stay quit!!!