Dating with a mental illness

[Starfish]

I have borderline personality disorder and haven't dated for about 5 years due to a previous abusive relationship. I'm pretty symptomatic in my private life, but do a good job of hiding my emotional dysregulation and other symptoms when around people I don't know well.

I've recently started talking to a guy, we've been on one date and get on well, but it's always in the back of my mind that if we continue to date, I'm going to have to tell him I'm unwell, which absolutely terrifies me. BPD is so stigmatized, how do I explain it to him without sounding crazy? And when's too soon to disclose a mental illness? He'll find out sooner or later considering I'm covered in self harm scars (easily hidden with sleeves) and that's a whole nother thing...

I know I'm probably over thinking this, but it's making me so anxious and I don't even know if it's just my abandonment issues flaring up or what. I'm just exhausted. I've been obsessing over this since I met him, which is making me feel more crazy.

When is is the right time to disclose a mental illness? Do I bite the bullet and just tell him or do I wait?

My fiancé has no experience with bpd but he said it has no bearing on his love for me. When we began dating I didn’t say much about it but things became serious very quickly so I told him about my mental health. I also have a lot of scarring and he said so what? You are beautiful and it makes no difference to me is what he said. He realises that I must have been in a lot of pain to do it and he feels sad that I have had so much abuse and sadness in my life. I hate the stigma that goes with bpd, not everyone with it is manipulative, I’m certainly not. It helps that he is laid back, when I become upset and distressed he supports me but is able to not let it affect him if that makes sense. He is amazing!