the male always tries to get with her but she wants nothing to do with it
To me when you said this . I take it the male is harrasing her. If he was biting her then that would be considered attacking her. So if he is constatly harrasing her to breed since what you described is courting behavior. Then they should be separated. She might just get fed up one day and do some damage to him. Even tho the dock is big eneough for them both to use they are still forced to use the same one. That again is causing stress on the female turtle since she has to be in close quarters with the male