Charm, I had the nausea something awful. It didn't matter how much I ate, what I ate, milk, no milk, taking the pill right after a meal, a little while after or during the meal. It's listed as a side effect, so it stands to reason some will suffer from it.
I would not have been able to stay on Chantix with how the nausea was affecting me. Luckily, I read on these boards that some were having success with splitting their pills in half and taking them four times a day instead of two whole pills twice a day. Remember to take even a half with a meal and plenty of water!
This absolutely did the trick for me. The nausea was still there once in a while, but it was short-lasting and tolerable. I also personally much preferred taking several small "blasts" of Chantix throughout the day as opposed to only two big doses. I swear, I think it helped my cravings being able to take a little bit of Chantix right after lunch and before bedtime.
Whatever you decide to do, be sure to speak with your physician and let him or her know.
Best of luck