This ^^ shows her, you don’t trust her. For some people, that would be an attack on their integrity.
Even if it was your issue, you made it about her.
Your first big argument was an attack on who she is as a person. If she is someone who lives strongly by her morals, this is a big blow. Don’t get me wrong, I don’t think your a bad guy. I think you made a mistake. You said you have your own issues, but you have to acknowledge that you projected them on your gf. I’m not totally sure if this has anything to do with mental health and more about setting a boundary.
I understand you love her and want to support her. A lot of us supporters, believe giving space is showing our support and love to our partners.