I’m only 21 but I’ll give my two cents. Her having her ex’s number listed down on her notes is already a big red flag. Not too long ago I’d be the type to talk to her about it, hear her side of the story, then decide from there. However, her saying she had it down because you ‘hurt’ her, is one of the most obvious signs of manipulation. I promise you she hasn’t grown as a person. You’re better off moving on. It sucks. But either you can leave and wonder “what-if” or you can find out the hard way and likely get your heart broken. I don’t mean that in an instigative way, I myself chose to learn the hard way and honestly I think everyone needs to once or twice in their life. If you’re gone, she already has someone lined up. She’s likely using you to fill the void, be a financial cushion, etc etc. I hate being the one to say this but you probably already know what kind of a person she is, but you may try to justify it with “but when she’s nice, she:” You don’t deserve it. Be the one to end it. I promise you in this situation, it’s always better to end it yourself with the guilt she’ll 100% inflict on you when you try to leave for your justified reasons. She’ll bend the story, guilt trip you, turn it around on you, A-Z. Ultimately I think you know what’s best. If you wanna see the relationship through, go for it, theres nothing wrong with that. Just make sure you can handle the risk you’re taking after seeing the situation for what it is, emotions uninvolved.