He sounds so confused about how he feels.
The problem is he feels like he needs to be there for his child and give this relationship a chance but you can not be in a relationship when he wants to be with you.
He can still be a dad and not be with the mother.
He needs to be happy and I feel his feelings are very strong for you. What I want you to do is to keep contact with him.
He misses you, that is very clear.
I feel that if you keep in contact with each other then he will see his feelings for you are strong.
You have a good relationship with his children and that is very important.
I feel he will realize that he needs to be with you.
His message sounded like he wants to be with you and that he knows he belongs with you, so he just needs to make that decision.
Some times when someone comes back in your life and you have a child you feel like obligated to give things a second chance, but if they do get back together, then he will realize that he no longer loves her because he is in love with you.
He will then know he made a mistake and try to get you back.
This is why I feel you should keep contact with him, basic contact like maybe text to ask him how he is doing. He is not afraid of his emotions and he is very honest on how he feels.
This is good because you do not have to guess.
You know how he feels, but he is confused. I feel he has been honest with you since this all started, but I do not feel he has feelings for her, he knows he loves you and is in love with you. He is going to come to realize that his relationship with her is not going to work out because he is in love with you.