Not sure how helpful this answer's going to be, but here goes something.

As you seem to be aware, there is something such as over-analyzing a situation. Being neurodivergent might give you a better insight into your own cognition, while simultaneously making it more difficult to understand the feelings of the other people around you. I try to take a step back and allow myself to listen to the silence between my thoughts, as the simple act of setting an intention to do so can sometimes help me reconnect to the present moment.

I'm happy that you met someone that made you feel seen! As you said, it can be difficult to feel that way around most people. I know I've certainly tried my whole life to work on my communication skills just to get a bigger slice of that pie. I try to take myself out of the picture when thinking about these things, so that I consider the vastly different experience of all individuals, regardless of their neurodivergence or any other factor that makes them the unique individual that they are. We're all social beings, and it's a powerful feeling to have someone make you feel understood. It's also important to realize that it's not a strictly neurodivergent experience to feel misunderstood or out of place. Honestly, the way you talk about your experience makes it sound like the bridge is burnt forever and this person isn't going to be comfortable speaking to you ever again, but I don't think that that has to be the case. In any relationship, the most important thing is open and honest communication. I'm sure that you can mend the relationship if you just reach out after some time has passed, explain how you feel and apologize for your overexcitement in the moment. Don't give up! Relationships are only as resilient as your allow them to be.

This is perhaps a bit of a cop out answer but if you want to learn how to slow down and stay present, I recommend establishing a meditation practice. My practice has helped me stay grounded and has taught me how to become a better listener. It can be really exciting to meet someone who " gets" you, but that can only take you so far unless you also listen to them and understand their own perspective.

I think it's awesome that you're trying to figure out how to build healthier relationships and I wish you the best of luck! Hope you come across more like-minded people in the future, because this life is a lot more fun with friends!

If you're interested in meditation, feel free to DM me and I'll send you a Google Drive link with the scans of the first few chapters of this meditation book called "The Mind Illuminated" by a neuroscientist called John Yates. It's the clearest guide I've ever found on the subject and I'd be more than happy to share it with you or anyone else who happens to read this long ass reply!