A.S.
There's no magic recipe for sleeping kids. Each one sleeps different and needs different things. There are however way to help them through those things. If he's not nursing in the night (both my daughters cut out eating in the night on their own about 6 months old) he's probably still used to that physical contact with you. I know both my girls are like that. The thing is, we as parents inadvertantly create habits for our kids.
I'm not much of a parenting book believer, because I don't believe that it's a science but rather an adventure that we're all destined to find our own methods and tricks. But I've read my fair share and gleaned small bits of advice.
The best I can suggest is that you need to sleep train him a little. I am not at all suggesting to cry it out! I do not believe in that method, if you do that's ok, but for me I just feel that it might cause my daugthers to not believe i"m there for them. And whether they are 1 month or 70 years old I want them to trust that in a pinch I'll be there.
Anyways, when he wakes up and you decide that he isn't going back to sleep himself, go in, pick him up. As soon as he's settled put him back down, if he cries (not just stirs) pick him up, as soon as he's settled put him down. Keep doing this until he stays down, I usually put one hand on my daughter (who's 13 months) shoulder and the other hand I pat her bum. If you sing, keep singing etc. He'll eventually realize you're there but your not going to give in and hold him all night. It'll take a while, maybe a week or a little more but eventually he'll figure it out. You may have to go in once, or stand at the bed edge and sing/shush him but he'll figure it out. (read the baby Whisperer, she was a HUGE help in our sleep patterns in our house. My oldest was getting up even at 2.5 years old, she has gentle but effective methods.)
Whatever method you and your partner chose (because he needs to follow through the same!) stick with it. Not just a day or a week, but give it at least 3 weeks try. If you keep changing you'll just send mixed messages. Just know as he grows up his sleep patterns will change and you'll continually be adjusting, teething, bad dreams, holidays, and potty training will all effect his sleep and yours. And bad habits creep in no matter how hard you try (I'm doing the following proceedure with my youngest again because she was teething when I was very ill and I got into the bad habit of letting her sleep in my bed in the middle of the night so that I didn't have to get up...it's changing back again) but they can be broken and sleep can be had.
Sorry this is so long, sleep is just an issue close to my heart. And whatever happens always, always remember these are the moments you can keep him safe, hold him and love him. He won't need you to rock him to sleep at 16 and one day when he's grown and gone you'll long for the moments he was in your arms, because it's only then as a momma we truly know they are safe!
Good luck, I hope one or more of us have something to say that makes this easier for you! Let us know how it goes!