WTF was that?

I’d been dating a girl for 4-5 months and it was really fun and great. We didn’t have a single argument, but we ended up breaking up because I couldn't give her as much time as she wanted. After 6 months of complete silence, she texted me out of nowhere and asked to talk. We decided to give it another shot. She told me she had missed me terribly and had never felt that way about anyone else. This time, I gave her 100% of my energy and paid attention to every little detail. We lasted only a month. She suddenly told me her feelings were gone, and now she’s already talking to another guy. WTF? I was her first boyfriend and we did really well, as I said not a single argument or anything