Without knowing a bit more about your boyfriend's background it's hard to know how to answer this, but I'm going to give you the same advice I would give my daughter (as yes I have a grown child your age).
My concerns with him being jealous are two fold. The first is I am assuming he doesnt have children. If he had children he would understand that keeping the bonds with parents is important for your child's current and future growth. If his father chooses not to come than that's his problem.
I would tell this current boyfriend that he needs to understand that the involvement of your child's father is not only important to you but is important to your child. You also need to maybe look at not seeing this person, if he cant understand the importance.
If he does have children and still can't see it, than this is defiitely NOT the type of person you need in your life. If he has children and cant understand than I would question what kind of relationship he had/has with the mother of the children, etc. Also, I would listen for keys like how well he treats his mother, the server in a restaurant, etc.
It's really important that at this early stage of separation, you have someone that is supportive, NOT someone who questions your motives of having your ex-husband and child's father in the picture. He needs to understand that like it or not, this man will ALWAYS be around due to the fact you had a child together. If he can't accept that or feels the need to change it, sounds like you need to step away from him.
You may care about this new man, but if he doesnt empathize and understand, he may need someone without children or previous attachments.