She follows you when you move??? Clingy with boundary issues -- and subtlety will never work with that kind of person.

1. You need to stop talking to her NOW.
2. The next time she does this, say LOUDLY "I told you not to talk during class." So everyone else hears it's she not you -- which only works if you're following 1.

She'll either go into a snit and refuse to talk to you, period, or blather 90mph denials. Either way, she can cling to/stalk someone else.
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