She keeps on insisting on contacting her on her personal mail, to send me photos and tell me about herself but I already told her multiple times that I am not interested.
So sorry to learn that this is happening to you!
You did right by asking this person to stop, however, they persisted! Follow this link for a video and guide to help you block this person so that you can get back to enjoying Twitter!!! :-) https://help.twitter.com/en/using-twitter/blocking-and-unblocking-accounts