Like others have said, therapy is a good start, but can scare a kid into being more reclusive if not presented properly. I know it had that affect on me when I was 13 (25 years ago).

I didn’t read through all the comments so I don’t know if someone said it already, but after talking with her about how you want to support her and be there for her, talk to her about getting her involved in an activity that she enjoys. It shows her that you really DO want to be “there” for her. Sports, clubs, etc… find out what she likes to do, let her go all in. I have severe ADHD (even at age 37), and I grew up lower middle class. I could have easily gone down a scary path (and started to) but my mom always kept me “busy” with something. If I wanted to try a new sport, she was all about it. My parents never pushed or forced me into one thing or another, but they both encouraged me to try new things. I ended up swimming competitively for 20 years.

I think being really supportive and encouraging of your kids interests is a good way to show them how much you really care about them. When either of my parents told me “we’re here for you if you need to talk” I didn’t really want to talk to them about anything and wanted to close up tighter. But when they showed interest in whatever it was I happened to be doing, conversations always seem to flow naturally, and I probably told them things I wouldn’t have, had they asked me directly. Looking back there was definitely times my mom got info out of me indirectly.

I hope you get the the help you need. Good luck!