Is it strange that I'm really drawn to (and maybe a little obsessed with) someone I just met?

I’m an 18-year-old female, and I've struggled to make friends my age ever since kindergarten. Even now, I find it challenging to understand my peers and connect with them, and I have no idea why. This has caused me a lot of anxiety whenever I try to build friendships, and I'm constantly worried that any relationship I form will eventually fall apart because I just don’t know how to connect with people. Recently, I met a guy online who is two years older than me and lives in a neighboring state. We had a long and meaningful conversation about our life situations and challenges. He was incredibly humble, grounded, wise, and empathetic. I’ve never felt such a strong connection with anyone before. I was genuinely surprised that he wanted to listen to my struggles with family issues instead of just ignoring me. We’ve been chatting for a few days, though not as deeply as that first conversation, and I can’t shake the fear that I might come across as annoying or that he might pull away once he realizes I’m a bit quirky. I really dislike feeling this way because he has a girlfriend, and the last thing I want is to interfere in their relationship. But I can’t help feeling a bit obsessed with the idea of not losing someone I’ve just met. It seems ridiculous, and I feel like a creep for being anxious about it. Honestly, it makes me feel down because I think I’m fixating on him—not because he’s particularly special, but because I’ve struggled to make close friends my age. When I find someone cool, I become anxious about keeping that connection. I worry that this might be unhealthy behavior, and I fear that my emotions are leading me in a bad direction. I hope that by acknowledging my anxiety and obsession, I can learn to manage them better. But this pattern has been a part of my life for so long, and I’m scared it’s something I can’t change. Any advice would be appreciated. :’(