Why am I such a bad person?

Hello. I'm 15M. So let me go straight into it.

I dated a woman, it was a long-distance relationship. She's 26 (yes, really). And yeah, that happened a month after I broke up with my mentally-abusive (also a long-distance relationship) ex, she was 30.

So yeah, once (now I'm talking about the woman that's 26 and gonna be talking about her for the rest of the post). I made a post, it was here, on reddit. And I was just confused with what am I doing. Cause after the relationship with the woman who was 30 ended, I told myself "Okay, no long-distance relationships. No dating someone who's so much older" And yeah, I was there again? There were also some other things, but she was treating me very nicely.
After some thinking, I sent her a message about how we can't be together, and how I appreciated her, etcetera... And blocked her

Apparently, I didn't block her on whatsapp. So she texted me there a few weeks later, saying something like "I miss you, can we talk?" And we started talking again. She was quite flirtatious. And I didn't give in as much, but sometimes I did and then became cold again. So that was very confusing of me. I was (and still am) confused about this situation.
We've had many conversations about this, and never really got anywhere? I just told her smth like "I'm confused about this, I really don't think we should be dating" and she was "Yeah, we don't have to. We can just have fun" and I responded "Hmm, okay"

And yeah, this kept happening. Until today, it looked like it was our last conversation. She said "I'm done trying to keep fighting for being in your life" and that message. It's a bit confusing to me? But I get it.

I was confusing her non-stop about this. And instead of saying "Ok, this is over, we're not talking" I just wanted to talk.

I feel like an asshole. And just... frustrated with myself.