S.B.
My son went through a bit of this around 4 as well. He was never a good sleeper. I didn't want to make it some dramatic, scary thing for him, but I really need my bed and sleep back!! We went through every night light and table lamp to help him be more comfortable. Nothing seemed to work. He liked having his overhead light on, dimmed. The problem was that for some reason the switch would slide up over night and make him room bright. And on the rare occasion he did sleep through the night, he was still cranky. I think the lights interfered too much with his sleep. A lava lamp helped us a great deal. It seems to light up his room well enough to make him comfortable and less afraid, but it's dim enough that he sleeps well. And nights when he "can't sleep" we tell him to watch the bubbles. We hung a flashlight by the door and he used that for the restroom and to get to our room.
We changed the routine a bit. I no longer stayed with him while he fell asleep. I tucked him in and left. I often told him if he stayed in bed, I'd come back in and check on him. Which I did IF he stayed in bed. But it was short and sweet. A kiss, a pat and I left. Then we talked about how he had to start staying in his own room at night. That it was ok to be awake, but he had to learn to stay in bed. We talked about it for two or three days. Then the next night, I told him he needed to stay in his bed. Of course he came into our room. I let him climb into our bed with the warning of five minutes of cuddles. (Don't doze off...or this doesn't work ;). After five minutes it was time for his bed. The first three nights, there was a bit of crying and some hysterics. And I did the same technique of telling him I'd come back if he stayed in bed. Most of the time he'd be out by the time I came back. We just kept weaning from there. After we could get him back in his bed with out the tears, then the cuddle time went down to three minutes and seeing if he could get in bed without me walking him there. Then it was a quick cuddle and back to bed. Now he rarely wakes us up. If he does get us up, there is usually a valid reason.