I'm really sorry you are not able to have a true family. I can hear how much you long for that. But today you do not have a partner and your baby does not have a father.
The man you love loves drugs. And although you believe you are the only good thing in his life, from his point of view,drugs are the best thing in his life. He loves them more than he loves you or the baby. It is the way it is, with addiction.
Did you get some help for yourself while he was in Indianapolis? Do you have a support system of other people in codependency recovery? (I am assuming you are supported in your own recovery from drugs. I'm so glad you are clean for your child).
We pretty much become automatic codependents when we love addicts, and it makes us lose our minds. So you'll need some help keeping yours. You'll want to be able to make the best choices for your little child.
Welcome to SR. Many people here will offer you excellent feedback.
God bless you and the baby.