Have you read Tracy's toddler book? She describes a similar issue with a 14 mo old who is nursed to sleep and during the night (it's on p 254). That's a great place to start for eliminating the bottle and teaching him independent sleep. Odds are, when he isn't relying on the bottle to sleep and knows how to do it himself, his night wakings will be less frequent.
Something else jumps out at me here...why is he having trouble going to sleep at night? Is he fighting sleep? If that's the case, his naps may need to be adjusted. One of the clues that LOs are ready to transition to 1 nap is difficulty going to sleep at night. If that's what's happening, you may want to sort that out first before dropping the bottle...although he may be so tired that he may not fight you on eliminating the bottle...It also sounds as if he's been left to cry at some point? If so, it may take a bit longer to re-establish trust and get on track, but it certainly can be done! Keep us posted!