look, i know there's pressure to get to them to sleep alone, lots of folk around you might be asking if he's sleeping well YET or talking about sleep training their own little ones but 7 months old is still really little.
However you get him to sleep now - bfing, singing, rocking, dummy reinserting, sushing, patting, driving, walking etc - you won't still be doing it when he's 16 years old, and it'll stop a lot closer to now than then. the intense baby stage doesn't last forever and babies learn to sleep whether or not you attempt to 'train' them. Isis online provides information on normal sleep patterns in infants.
So put thoughts of others' unrealistic expectations out of your head, along with the notion that you've failed him (nursing to sleep is not somehow a uniquely bad sleep habit as opposed to other methods mentioned , in fact, its the biological norm).
What works for your situation, do you get enough rest? If you are happy with bfing to sleep then carry on - maybe work on your position to get more comfortable though! If you don't like nursing to sleep or want to see if other methods get you more rest then go ahead and try it. Cosleeping is one strategy, if it doesn't work for your family then try something else.
The caveat is that stopping nursing to sleep does not guarantee he'll suddenly sleep through the night. if he's not ready then you'll just have wakings to deal with in other ways. some formula fed babies in my postnatal group take bottles overnight and babies whose parents have stopped the night feeds still often need resettling.
You say he 'obviously doesn't need the milk' - maybe he can go longer without food, but if he's taking decent milk feeds at night then he'll need to adjust his daytime intake of milk to compensate if you stop them. If he's comfort suckling, then he might need to still wake for reassurance - though other methods of comforting could work.
I hope I've said something useful, fwiw, my 5.5month old also sleeps in a bedside cot and i nurse him in the night. its not for everybody but it works for us, and I can't see us stopping anytime soon. I use a long 'body' pillow to support me in a comfortable position (ish).