I've never had any problems hiking solo, which I've done for the past 20-some years--I can't keep up with most people any more and I am more at risk for falls when I'm pushing to do so. I've never had any unpleasant encounters with other people.

That being said, I'm a lot more careful hiking solo--not because of people but because of no help should I have an accident. I finally started carrying a Personal Locator Beacon to keep family and friends off my back (I call it psychological weight reduction). However, at my age (77) an accident would probably put the finish to my hiking career, so I remain extra careful, especially when off trail. Aimless is exactly right about the risks of being solo being greater than the risks of being female.

I also email my itinerary to a family member whom I can trust not to panic and call SAR if I'm a few minutes overdue. I call her when I'm out of the wilds and back in cell phone range. I insist that she give me 24 hours after I plan to come out, in case I'm delayed--I have the gear to last that long and, of course, if I have a serious emergency where I can't self-evacuate, I have the PLB. This gives me plenty of flexibility if I want or need it. If I'm dead (one situation in which I couldn't push the button), it doesn't really matter!

EDIT, LATER: Maybe if you take a SPOT and sign up for the tracking feature, your BF will be happier?