Quitting smoking

Anyone else finding it really hard to quit smoking? I feel so guilty for smoking but finding myself severely stressed and cranky when I go long periods without!! I used to smoke about a pack of cigs in a day or 2 but now I only take a couple puffs here and there but can't seem to stop! I don't want to hurt my baby with smoking or by quitting! Is there any way to make it easier? Any advice ladies?