The PK380 is much easier to rack the slide. That makes it much easier for a woman to operate. It is also smaller and better suited to a woman's hands. I recommend the PK380 for a woman. It is a safe bet. Look for good deals on used PK380's. You can find affordable .380 ammo at USAammo. Watch for deals on Remington UMC at sporting goods stores as well. Check out gun-deals.com for ammunition pricing from various vendors. For self-defense ammo in .380 I think the best is MagTech 85gr HP...one of the best values. Also Federal Premium HST and Winchester T-Series are great rounds. Any of those rounds are very deadly.
Good Luck, and get trained and a lot of practice and by ALL MEANS follow the safety rules. We just had a guy shoot himself in the hip down here in Virginia while removing his seat belt and he died. Never forget that a handgun is a deadly weapon and negligence can lead to death.