She lied, but I still love her

So me and this girl dated for a little while but we both had a lot going on in life and I was too mentally drained for a relationship and she said she felt the same so we planned to stay as just friends for now and get back together in like a month or so. a month later she ignores me in school and already has a new partner and I'm really happy for her and their super cute together but it's like we never even happened