Okay guys what happened here?

I met a guy two months ago who told me he "didn't do relationships". But he started to change his mind, I believe. Out of nowhere, he began telling my good friend all about how cool he thought I was. And how excited he was to hang out with me again... I found this odd, but I went along with it.

See, he showed me a lot about himself and his life, and I gained interest. I thought he was cool and wanted him to like me, so I began to adopt his habits and like the things he liked. But something happened. As soon as I began flirting back with him and expressing my new love for the things he loved, he became distant. We went from texting multiple times a week to nothing at all. I got worried a few nights ago, got a friend to speak to him for me, and found out that he got a new girlfriend the very next day.

He was apparently speaking with her when we first met, but wanted to "keep his options open" so he wasn't dating her officially. I thought he really liked me. He said I was beautiful and fun and he loved chilling with me! Do you think I chased him away when I started to get into the same things he was? When I started to reciprocate the feelings back? What did I do wrong? Did he probably love her all along and I was just a fun thing?

I didn't cause any drama or hurt, so I don't know what the problem is. I am over him, but for closure, I want to know what you think about all of this.