Personally I do hike alone from time to time. I actually enjoy it. The time alone in the wilderness just seems to feed my soul and recharge my batteries. However, I only do this on terrain that I am comfortable with. I know my skills and I wouldn't go on a long scramble alone. This being said, it is always a good idea to have a partner.
Being in the wilderness puts yourself susceptible to certain risks. It is always safer to have a partner to help out in case something does go wrong. It really doesn't take much to sprain an ankle on loose rock or have something worse happen. Besides, a companion is always fun to chat with. I always seem to learn fascinating things about people when in the wilderness. There is none of that city B.S. People tend to open up and be real in the mountains.
If you don't have a friend who is into hiking mountains there are many other ways to get in touch with others who share your love for the mountains. Post a message on14ers.com or any other online place where fellow climbers hang out. Chances are you will find someone into hiking with you. Or ask around the local outdoor store. They may have ideas about local people who are looking to hook up for a hike.
Check it out and stay safe.