Honestly, I've never had a safety issue that was dependent upon my gender. I find camping to be much safer than my regular life.
If you're looking to rob, rape, murder, etc., you're probably not looking at campgrounds - in the summer, they're pretty well filled and folks are outside and within shouting distance; in the winter, the campers are far and few between (enough that you could be hiding behind the tree with your ax for quite a few days before a victim shows up). Not really a prolific hunting ground for the bad guys.
During a camping trip not too long ago, in the winter, I stayed at a campground where there was one other camper (a solo male). The first 1-1/2 days, it was just the two of us in the campground. He came by my site whenever he left the campground to ask me to "watch his stuff"... The 2nd day, a group of two couples set up camp in the site next to his. Around dinner-time, they lit their campfire and sat around it listening to music, talking, eating, etc. A friend had come up to visit with me and we took a walk around the campground. As we passed the group, they said hello (we returned the greeting) and went about their business.
As we passed the solo male's site, he rushed over to us and said he was packing up to leave because he was sure those people were going to cause trouble. He was sure they were a bunch of wild young men who came out to get drunk for the evening and who were looking to pick a fight with him. I explained that they were two couples, had a full camp set up, had their fishing boat, and did not appear to be town kids looking for a party/trouble. He decided to stay the night, but chose to take down his tent, get everything ready to run, and sleep in his truck.
As we walked away, I asked my friend "as a solo female camper, should I be worried about my safety considering this man was obviously very worried about his safety?" Needless to say, the man left the next morning out of fear - I stayed for the rest of my planned stay and never had a problem.