OP, if he is using his " need for a baby " as the explanation for no longer loving you. It is at least possible that he has found someone with whom he wants to have a child.
No matter how much you want it to be so, you cannot make someone love you when they no longer love you .
You may have thought of him as your best friend, and you may even be or have been his best friend. He may on some level still think of you as a friend. What he is wanting to no longer be is your partner and your lover.
You must begin to plan for a future that does not include him. Regardless of what you may be telling yourself, your life did not begin on the day that you met him, and nor will it end now that he is gone.
You are a person in your own right. Your identity is not tied to him. Rediscover those things that interest you. Paint the room in whatever color that makes you happy. Do not discuss your daughter's visits with him. Let their relationship evolve as it will without your knowledge or input. She is an adult, and he has separated from you but not necessarily from her.
Begin seeking legal advice, and find a counselor for yourself if necessary. You denigrate your life by wanting someone who does not want you.That my be a brutal statement, but your life has too much value to waste it grieving over a relationship that no longer exist. He was your yesterday, but it is up to you to create and control your tomorrows.