I solo hikie almost exclusively. I like to dawdle on the trail. I hike well used trails though, so, the arrival of help wouldnt be an issue.
As to gender issue, I dont think it comes down to a woman being any less physically capable of defending herself; I think it is the predatory nature of the male perp. Remember a couple years back, that guy that killed the woman hiker on part of the AT? She was a black belt, he was an older man, who appeared, to her, harmless. However, he overpowered her (in his words, he felt he was losing, and feared her escaping & him being caught, until she gassed out). She fought back, and lost. This had nothing to do with her ability, or her gender; she was taken completely by surprise by someone that didnt appear threatening to her; a fellow hiker. He spent a week with her, before killing her. He bonded with her; then murdered her. The man has no moral compass; his only thought was that "I cannot let her go, she will tell on me". So, even though he told her he was going to, and she believed him (she attempted bonding, but, as is illustrated, someone who is morally flat, you cannot bond with), he murdered her, in cold blood.
Then, about 10 years ago, there was ANOTHER murder on the AT; a double shooting; a man & his girlfriend. Someone just walked up to them & shot them (I dont believe the killer was ever found).
This illustrates that, the people who will do this, will do it. They develop a predator instinct; know how to lure someone into a sense of security, then strike. Sadly, they dont ever appear as a "criminal", they appear normal, and functional, just like any one of us. This is their camoflauge; we are their prey. Sadly, most of these predators are men, and their prey are women. They KNOW women hike alone on popular trails when its warm. Thats easy for them; no police, easy ambush site, you can disappear into the woods. The best advice one can give is to be on your guard at ALL times. Its sad, but this is reality.