What I'm about to tell you, others have already said. I'll just emphasize it though.
He is too young. It isn't realistic at all to expect a cosleeping baby to sleep on his own at such a young age for any period of time, as he is attached to you. If he awakes and finds you gone, he will think you have abandoned him, and he'll cry out in distress. He won't have the object permanence to reason that you'll come back later. Babies can't think like that. If something is not there, to them it is gone forever.
Now, I know you won't want to sleep the same times he sleeps, as babies need more sleep than adults, but could he sleep in the same room with you with some white noise going on? Just a thought.
Babies are totally dependent on their caregivers. Expecting them to develop a form of independence at a young age is not realistic at all. Mainstream parents would like you to believe this, but this is so unnatural for both you and baby. He can never be too dependent. Just remember that. He can't even cope with the world around him, emotionally or physically. He doesn't have the reasoning skills that will enable things to make sense to him. He can't communicate with you in other ways except through crying. He can't fend for himself and care for his own needs. He needs mommy for everything. I mean everything. I know it may get tiring: but just hang in there, girlie. He'll thank you so much for it. It will pay off so much later.
I understand why you thought that way though, as I'm sure baby-wise people tried to make you feel bad. But, please don't listen to them. Nurse to sleep as long as you can. Don't stop it. Time with your baby is so fleating. Don't rush him to be independent. Before you know it, he'll be independent enough to leave the nest, and you'll be lucky to hear from him twice a year. So enjoy this time while you have it to bond and give him all the affection he needs to become a viable and secure adult, and stay strong. You can do it. We root for ya.