I am sorry for what you are going through. A few things jump out at me in your post:
You have been dating this guy for 3 months. Only 3 months.
He has an addiction to alcohol, meth and heroin.
You are in tears daily due to the way he talks at you or down to you.
You are desperate for communication from him.
He would be angry if you didnt let him know you are at the hospital but there is no communication at the moment due to him being in rehab.
You feel alone and empty and terrified he will not come home to you and your daughter.
It seems like you have invested all your emotions in to a man that is unavailable in many ways. From your assertion he has multiple substance abuse issues and is now in a rehab. You have only been with this person for a few months and have invested your whole entire being in to him. I would understand some of this if you two were married or dating for a long period of time.
Have you considered talking with a professional about some of the issues that you may have surrounding abandonment, co-dependency and relationships?
Just a thought
I would really consider looking in to getting help for yourself.