I'm the exact same way. Being in the dark is scary as Hell for me. I have a nightlight in my room and bathroom that are never turned off. Like you though, if someone is with me I feel safe with, I'm perfectly fine.
I prefer sleeping in the dark really. I used to sleep with my ipod on all night though because I have a hard time getting to sleep at night, always have. But when I moved in with my fiance I sleep better. But the house is so quiet in this small town that it gets creepy at night if he falls asleep first and I get up to go to the bathroom when it's pitch black. I always run from the bathroom back to our bedroom. We sleep with the door closed and locked. We're both kind of paranoid.
It is a common problem that faced by mostly persons in world. I also feel scared in night sometimes. It is a phobia that is known by scotophobia.
every night i have to sleep with the lamp on. (if i end up going to sleep, either way it stays on) electricity bill is up, but hey, no fear.
There has always been a fear of what or who may be lurking in the dark. When venturing back from the basement, I turn off the lights and run like hell up the stairs. Also, when going to bed I have a tendency to sprint from the doorway to my bed so things in the dark can't get me...it's stupid. But you're definitely not alone.
I can never sleep without a light on, or a t.v. on.. I panic otherwise.. Odd, I was never like this.. Only the last few years have I been..
I love the dark. For the most part. I see more dark than light on most days. But I do have living terrors and horrors about the dark. They turn into storytime, of course. Scary stories are extra scary when they're real stories. "Based on true events" heh heh Don't worry, I won't story you.
I am also afraid of the dark. Or rather, what's in the dark. As was stated, if there isn't anything there, there's no reason to worry. It's gotten a lot better for me, I used to not go into the dark at all if I could avoid it, nowadays, I'll force myself to go into the dark if I have a reason to. There's almost always nothing there to fear, I think our minds just aren't fond of the idea that we don't know what's there, because if we can't see it, there could be anything there.