G.♣.
If you want to make a change because you don't like the situation the way it is, that's one thing. But you haven't done anything wrong. This isn't a bad habit and you didn't "cause" this. Your baby is only 9 months old. It's perfectly normal for him to want to nurse at night. It's perfectly normal for him to prefer co-sleeping. You haven't done anything wrong, and letting things continue the way they are is ok, too. Our boys co-slept with us until they were about 18 months, and after that they were still welcome to come into our bed in the middle of the night.
If there is another bed in the house, you can sleep with your son there. That might help you all get a good night sleep. You could also put your son in his own bed at the beginning of the night and then bring him to bed with you when he first wakes.
Unless you are drunk or on drugs, you are not going to roll over onto your son. That is a myth that is very believable, but it really is a myth. People are actually much more aware at night than you might think, and unless you are somehow impaired, you really are not going to roll over onto your son. Do you roll over and try to roll onto your husband at night? I realize your son is smaller, but it really is extremely unlikely.
Relax. You haven't done anything wrong. There are other things you can try, but it's very important for you to know that you haven't done anything wrong, this isn't a bad habit and loving and comforting your baby is never a bad thing.
A really good book to read is "The No Cry Sleep Solution" by Elizabeth Pantley. She has lots of great, gentle ideas that you can try to help your son sleep on his own - if that's what you want. Again, what you are doing is ok. But if it isn't working for you, it's ok to want something different.