My gf of 2 years had sex with 8 or more different men in one week……. 3 weeks before she met me……..

Sooo basically I’m kind of a snooper, I know it’s wrong and I shouldn’t butttt I go through my girls phone sometimes. To be fair we both have each others passcodes and I tell her she can go through mine anytime she wants. Me and this girl have the most perfect relationship honestly her family loves me, my family loves hers, we’ve been living together for 3 years, we barley fight at all, we take care of each other and every thing. Anyhow, reading through some messages with her friend I found out 2 weeks before she met me, she went on a vacation that I knew about already, but what I didn’t know is that she had sex with like 8 different guys, she had a threesome all dudes…..AND a foursome ALLEGEDLY all dudes…… (allegedly cuz in the messages it says it was planned but there’s no clarification days later if anything acc happened with the foursome but the threesome definitely did). Verbatim she says in one message “ I had sex with a new guy every day this week” Everytime I ask her about the trip the story changes, its really messing with my head and tbh I’m really debating on breaking up with her. Probably tmi but she was r worded at 19 and I have a lot of sympathy for her and her actions because of that, but I can’t help but believe that I don’t deserve to be with someone who could have sex with that many men and look me in the eye and lie about it. She’s lied to me before about a year into our relationship, she lied about a man she said she never hooked up with, come to find out, one day when she was going out to do some work for her business, she acc messaged him and asked him to hang out, and turns out it was the guy who took her virginity and she had a long term relationship with. When I questioned her she told me part of the truth, pretty much just that she did have sex in the past with him and they dated but she told me she just messaged him to give her a ride lol, and I had to find out the rest on my own about him taking her V card she didn’t tell me that. Other than all of this this girl is so perfect, she even agrees to us having an open relationship on my end and closed on hers, she is bisexual and wants to have threesomes with woman with me, and she cooks cleans and literally does every and anything u can think of for me. I think my question is how do I look past her previous actions and move on if she won’t tell me the truth? And is all the lying a red flag or is she just scared to lose me?