Having to pick one child's happiness over the other

My daughter right now. I am the worst mom right now. I have 3 kiddos. My daughter is 16, my son is 15 and my younger daughter is 13. It's the 16 year old one who hates me. She feels like I put her brother's happiness before hers and in a way I did. I made us move and her change schools because my son overdosed in the bathroom at their school. I had no idea he was doing drugs. I had no idea what he was going through at school. He's been to rehab and I decided he didn't need to be at that school anymore. I don't want to go into everything I found out when he was in rehab but it's a lot. And honestly my daughter doesn't know everything. He started doing drugs when he was 14. He told me at family therapy while he was in rehab that he was using drugs to heal from an SA that happened by a classmate that I didn't know about. Then there was other stuff with people going on at school. A lot of bullying. Some physical assault at school that he never told me about. Some things which has lead to me pressing charges against some students. There's a lot that went into why I made this decision. There was only one high school in our town and everyone was already talking and I figured there's no way he's gonna stay sober while still living there.

My daughter thinks I just moved them because of him overdosing. She knows a little about the bullying. She doesn't know how bad it was or about the SA which is his business. I have tried to ask her for a mother daughter day but she said no. She's so angry at me and I hate that she feels like her happiness just went on the back burner. I wish I could make all my kids happy. I wouldn't say any of my kids are happy right now except my 13 year old who really didn't care that much about the move. My son's depressed in general and my daughter is mad. I feel like a terrible mom and no matter what I do I can't do anything right.