For most purposes, a woman who has torn her hymen independent of sexual intercourse is still considered a betulah (virgin).
So long as she is not a divorcee or a convert, such a woman may marry a kohen. Even if she did have prior intercourse, so long as it was with a man she would have been halachically permitted to marry (i.e., not a close relative, mamzer, or non-Jew), she may still marry a kohen.
A relationship that did not include intercourse would not affect her ability to marry a kohen.