M., do you want to co-sleep for the next year or more? If you do, than let him sleep with you. Many families co-sleep.
However, if you really don't like co-sleeping, if you want your bed back and only share it with your husband, then stop doing this. I think that you feel that you cannot allow your baby to fuss. That's not true.
Keep a warm blanket under him while you nurse. The blanket will be warm from his body. Put him down in the bassinet along with that warm blanket so that his sleepy body doesn't touch the cold bassinet. Don't wait to put him down totally asleep. He NEEDS to know that you put him down. He needs to get used to falling asleep without laying on you.
Plenty of babies do this. But their moms actually teach them to do it by not tip-toeing around during their daytime naps. They make noise, play music have the TV going in another room, have lights on. They even flush the toilet. That helps baby know the difference between day and night. At night time, things are quiet, the room is dark, you don't come in and play and talk and enjoy. You feed, you put him down, you leave. (Or get back in your bed while he is in the bassinet.)
The way you do this is to put him down still groggily awake and let him cry and fuss. You can stand there a little bit and pat him and quietly "shhhh" so that he knows you are there. But let him learn to "work it out". Letting a baby cry is not the wrong thing to do. You can soothe him a way DIFFERENT than letting him learn that he can make you keep him in bed with you.
You just have to decide if you are willing to train him by expecting him to stay in the bassinet. You can take the time to come in and pat him, leave for a few minutes, pat him again, NOT picking him up at ALL, and let him figure out that he can drop off to sleep in the bassinet, or you can end up co-sleeping. In a year, you'll be on here begging people to help you get our baby out of your bed, and it will 10 times harder to do.
Do it now. It is so much easier now than it will be a year from now.
Dawn