Transcript for How an Israeli conman's alleged victim says he swindled her out of $200K
Reporter: He was handsome, charismatic and seemingly wealthy beyond measure. For Celia, it was an easy decision to swipe right. This guy suddenly comes up on my phone. And you can see he lives a very different life than what I'm he had some selfies. A picture in a nice car. You could see that he was a private jet. It was an overall package. Reporter: The 29 year old grad student studying in London says she was immediately swept off her feet by Simon and swept into a high-powered world of luxury. Just his aura and charisma. Reporter: Most first dates don't end with a flight on a private plane. You go to Bulgaria. I was texting my friends at the same time, I don't know what's going on. Reporter: You had a nice time. Yeah. Reporter: And then you came back to the uk. And what did you think, it was going to continue? I was starting to feel like, okay, this guy actually is really nice and funny. And yes, someone that I could date and, like maybe have something with. Reporter: But her dream of finding Mr. Right went horribly wrong. I hate him. This is so horrible. Reporter: Celia says Simon told her he was an Israeli millionaire with a nickname the prince of diamonds. But he wasn't who he said he was. It just comes, I can't help it. It's just so painful. Because I hate myself, I hate that I did this, you know? Reporter: And according to Cecily, their brief romance turned into a real life nightmare. Cecily alleged he defrauded her out of $200,000, leaving her spiraling out of debt, suicidal and fearing for her safety. That nightmare now over. In June, Simon was arrested in Athens for using a false passport, following a joint operation between interpol and Israeli police. He managed to do this, because he is a great guy who pretends he cares so much for other people. So you want to care for him as well. Reporter: A lot of people might think if it was 3,000 or 4,000 pounds I would start to think I needed this money back, you let it get to 200. I know it sounds crazy, but I could see the sums he spent on my cards. Reporter: Simon is a 28-year-old convicted con man who previously served three years in Finnish prison for defrauding several women. Now he faces extradition to Israel where he was indietsed in 2011 on charges unrelated to Cecily on forgery and fraud. I see how much talk there is about the banks, and it's like, you're so stupid, you know. Reporter: Celia says she'd been lulled into sympathy by his declarations of love. I will support you. I will help you. And we will lift each other. You're nice. You're cute, you're sweet. You let me do what I need to do. And I really, really, really appreciate it. Reporter: For Celia, the relationship started out innocently enough. I thought oh, my god, I really like him. You like the feeling of being liked. Reporter: When do you consider yourself to be his girlfriend? I think maybe it was a month after that. Reporter: She says Simon told her that his job as a diamond dealer kept him traveling constantly. Their romance dominated by texts and voice recordings. I wish you a great and beautiful. Reporter: He stole away to London when he could. But more often than not he flew her to where he was, always alluding to an element of danger in his job that kept him away, jetting away constantly on private planes. How often would you see him on a weekly basis? I saw him in London the next week, and that's when it started that he couldn't come back to London because of the threats that he had been getting. Reporter: Within a week he was already saying to you, I can't come back to London, there are threats against my life. But he could get me to where he was. Reporter: She said Simon claimed to be under threat from unknown, nefarious enemies. A hazard of being in the diamond business. There wasn't anything that told you this is fake, this isn't real? Oh, no. I can't wait to see you. Reporter: Celia says that Simon surrounded himself with people who helped perpetuate the myth, even to send videos of him accepte self and his bodyguard in the hospital after they were allegedly attacked. Soon there was another strange element to his story. She asked her to extend her line of credit so that hotels would be booked in her name to keep supposed enemies off his trail. How do you go from someone who's presented himself as a wealthy man to someone you need to give money to? Protection. I know it's not right, but he needed my name as a cover, he said. Reporter: Protection from? His enemies, as he's calling Reporter: You just believed him when he said that? I know it sounds so crazy. I wish I could take everything back. When you have a bodyguard, why would this giant guy be with him if he didn't need the protection? Reporter: Celia says she relented because Simon promised to pay her back but payments from Simon were nowhere to be seen, despite his insistence that they were on their way. The amounts that he needs to be able to function for a week is just so much. It's never just a few thousand for us normal people, that is a lot of money, but for him, it's not a lot of money. Reporter: How could you have trusted him to take out that amount of money? Of course he has the money, so he will pay me back. You didn't even think that it was a problem when you were taking out the loans, because he was so sure that the money existed. Reporter: And you loved him. Yeah, I think that's the hardest part of it, like when I realized that he wasn't who he said he was, it was the love aspect, the person that I thought that I knew. And loved. He had just done this in the most evil way. Reporter: Suddenly, hero her romance was crashing down. They told me they had long investigations on him already and I was a string of four or five women. I almost wanted to throw up. Everything just came crushing down at once. Reporter: Celia alleges that Simon was continuing to run the same scheme that put him in Finnish jail just a few years ago, using Herman to fund his luxury lifestyle and lure other women into his orbit. A cycle doomed to repeat itself until his arrest. I had to be put into a psychiatric ward because of suicidal thoughts. I didn't see a way out. You lost your boyfriend, not that he just dumped you, it never existed. He was never a real boyfriend. Reporter: The news was amazing and she believes media attention was an important factor leading to his capture. Simon in statements made outside of court said he would go back to Israel and face what is waiting for him there. For now, Celia remains in London, trying to rebuild her life. I see a difference in myself when I talk to people. Reporter: Much less nave. Much less nave. Reporter: James Longman in London.
This transcript has been automatically generated and may not be 100% accurate.