It's not necessary for anyone to say "why don’t you just go out and find somebody more compatible?”

The alternative to being with that person is not finding another person. Maybe it's being by yourself for a while. Maybe it's dating a few people for a while instead of attaching yourself to another person.

As divine said, just because someone doesn't want to continue having a relationship with you it's not necessary to hang a label on them or diagnose what kind of attachment style they have. Nothing went wrong - she just decided not to continue with you. Maybe there's someone else on her horizon, maybe she wants to be alone. Who knows and it doesn't matter.

I'm like her - if I'm done and I've told you, you won't hear from me again. I doubt you are going to hear from her if she went to the trouble to tell you she didn't want to keep seeing you.