In need of opinions, help!

Has anyone else had trouble trying to quit smoking while pregnant? It's been a huge struggle for me. Some days I can go all day without one and some days I want to rip my hair out. NO NEGATIVE COMMENTS. I talked to my doctor about it already and she told me to be sure to slow down and I feel extremely guilty about it, but I wanted to see if anyone else has had this struggle? Its making me crazy. One again NO negative comments.