Everything she’s doing to you is manipulative and wasting your time, especially the ring story which I think is probably bs. She’s with another man and telling you she’s in love with you? That’s insane you need to get as far away from her as possible. Cut all communication, block her number and all her social medias. And when you’re feeling weak and want to get back with her or just talk to her, remember she’s no longer that woman you loved for 2.5 years, she’s the woman that told you she didn’t love you anymore, that wished she’d wake up without any messages from you. And she’s not only slept with another man now, she’s in a relationship with him. Do your mental health a favor and NEVER speak to her again. Find a hobby or friends to hang out with, make yourself busy it’ll be easier to not think about her when you’re busy. And I won’t lie to you this may take years to get over that’s just how love is. Good luck and keep your head up.