He's the only guy who has ever given me a warm feeling and not an anxious feeling. Where do I go from here? 30 M 28 F

I went through a lot of trauma in my early 20s because I got involved with someone who was a narcissist, and the first person I finally opened up too about this turned out to be the exact same way. That person's name was Zach. I liked Zach quite a bit.

After doing some healing, I met a guy who immediately gave me a calm feeling when I met him. His name was Michael. Michael and I talked for a few months, but ultimately Zach came into my life again and after thinking he'd finally changed, he only caused me more sadness.

I ended up not completely cutting Michael out of my life, but scaling it way back on how much we talked. Ive never had the desire to tell Michael my trauma. And I'm pretty proud of myself for that. But I'm grateful that I handled it in the way I did, and didn't bring him into it.

I'm healed now, and I have been talking to some guys on tinder, and some Ive met through mutual friends. But I've realized when I talk to them, they give me anxious butterfly feelings. And I don't really like that feeling. Michael has always given me a warm pit in my gut feeling. It's been like that since Day 1. And I was at my best with him. I wanted to be better, and move away/move on from my trauma.

Ive known Zach since we were 17, and Ive only known Michael for a couple months. Why is it so different?

Also, Michael and I weren't at the point of dating/being exclusive, so I didn't cut him out. I really liked him, and was trying to work through my trauma.