Maybe try time outs! It's what we have had to resort to! Here's my story;
We have had the same problem with our son ever since we transitioned him from his crib to a bed.(about 2 1/2 yrs old) 14 months ago!!!!!!!
I, myself, have some sleeping issues, I'm a VERY light sleeper and can have a hard time falling asleep or waking and not being able to got back to sleep which is why the just letting sleep in bed just doesn't work for me not to mention we only have a queen bed and it's soooo tight!
My son has only slept through the night 9 times in the last 14 mo. Started with just coming in once or twice then, all the while just walking him back to bed! (Super Nanny method) Then actually became worse as he became scared of the dark and monsters! We had tried EVERYTHING; Super Nanny method, Charts w/ rewards, taking privileges/toys away, locking our door ( which only led to him nearly breaking it down), melatonin(under Drs. supervision) never put a gate up because we already had taken the one down on the kitchen because he (little Jackie Chan that he is) could easily hop over it, even the tall doggie sized ones!!
Just a few days ago a friend suggested timeouts which she did with her daughter! Well, I started timeouts 4 days ago and the first 2 nights when he came in our room he got a timeout, night 3 I heard him open his door take a few steps then heard his door close! Last night, nothing until he came into my room this morn at 7am (also have a special night light - the good nite lite that you program for wake up time) saying "mommy, I stayed in bed ALL night!" My son is very social and isn't big on being by himself, I think just wants to make sure we are there!!
By the way, my husband and I both get him ready for bedtime and snuggle with him and spend about 25min reading books with him and reassuring him we are not far, just that WE ALL need our sleep!!
I sure hope this continues and may you soon find a solution that works for your family!!! Good Luck!!