Odds are you're being tripped up by your smoking triggers, which need identification if they're to be avoided. QuitNet is full of people with experiences similar to yours, who will understand and support your efforts. Discussing these issues with those who've already gone through them can take you a long way down the quit-road. The QuitNet community can encourage you to keep going when you feel like giving up, sympathize with you when things are tough, and help you celebrate your successes. Also, there's nothing like an understanding 'ear' to help cut through the often-confusing thought processes that can lead to slips and relapse. Finally, you may develop some lasting friendships with ex-smokers from all over the world!
If you are working with an online or telephone coach, reach out to him or her, even between your scheduled calls!