I quit smokng! (Chantix)

It's been 5 days now and so far I haven't lost my mind.  The last time I tried to quit I got to day 2 1/2 when I couldn't stand it anymore.  I actually snuck out of my house - children and husband sleeping - and went to the 24 hour store to buy a pack.  I felt like a criminal!

I kept putting it off.  My husband and I had agreed that we'd both quit and give that to our family as one of our presents to them.  But the grouchiness of the two of us combined was a bit much.  So I let him go first.  Actually I only sort of wanted to quit.  I felt so guilty every time I would light up  (outside only - and away from the children always) but it tasted so good!

This time I decided I needed help.  So while I was at the doctors office with my 3rd case of bronchitis this year I asked for Chantix.  So far so good.  The dreams aren't any stranger than usual, the dizziness comes and goes (side effects) and it keeps the craving to about the same feeling I used to get when I hadn't had a smoke in 10 hours. 

So now I'm wondering how long does it take for the Chantix to get out of your system and do the cravings come back super strong when you do?