Monkey hates to sleep- help

For all mothers out there of infant children and those who have been there and done that, please help.

My son absolutely and positively hates to go to sleep. I mean he is just way to curious and attentive to let his little body relax and fall asleep at night. He literally plays, babbles and pulls up on things until he passes out. He will take a nap during the day, but not at the same time and never if you just lay him down to go by himself. Part of this is my fault, because he still sleeps in my bed, which I feel absolutely awful about, but I also can't bring myself to let him just cry for hours and hours until he falls asleep- he is very persistent and can cry for hours without the hint of being tired. He also spends the day with his grand mother (my mother -in-law) who loves to lay with him when he takes a nap, so not only does he get it from me, she contributes to the problem as well.

We have a pretty steady routine, I get home from work and we play together, and then I let him play in his pen, or walker, while I fix dinner. At about 8:00pm he gets a bath and a bottle and after that he is more awake then ever. He usually does not end up passing out until about 12:30am. Routinely. The only way to get him to bed earlier is to rock him to sleep and I don't want to start another bad habit, so I let him run out his energy by himself.
I've tried putting him in his room after his bottle, but as I said earlier he just cries and cries and cries and cries, still being up until late in the evening.

Anyone else have this problem and what did you do? Is it all my fault? Don't worry I can take it.