Relationship with an addict.

Been with this guy for a while. We have children together we been through long distance to him getting diagnosed with bi polar and now drugs smh.. anyways when I found out I kicked him out and told him he needed to get himself help. Well he decided to get himself help in rehab and he is asking when he gets out to come home and he will be doing intense outpatient.. he lied he stole money. He got out of control. He thanked me for kicking him out and him being there to finally get the help he needs. Said he wants to prove to me and the kids that he can be a better him. I feel alot of it is talk because of the lies. He said he cant live out his kids. He doesnt want to drugs he want to be in his kids life. Anyways how do you rebuild a relationship from all of that? I'm nervous to let him back in. I dont know how to feel nor what to do right now guess just taken it one day at a time..