YWBTA. Are you kidding me? Based on your replies this was clearly a validation post but you aren’t getting the validation you wanted. You keep making excuses and defending yourself. Let me put it clearly: If almost everyone is saying you’re the asshole, then you are the asshole. You keep blaming everything on this 12 year old girl. You are threatened by and envious of a CHILD. It doesn’t matter if she’s pushing you away. You are trying to push her away but you are the adult and should be the one making an effort. You’re the adult. Act like the adult. Children usually don’t adore their step parents right off the bat. To her you’re replacing her mother and potentially her and this idea is only being reinforced by how you want to exclude her so badly. You need to make the effort to keep her in your life, not push her out.