Is my ex- girlfirend in a rebound relationship?

My ex-girlfriend of 3 years broke up with me 3 months ago, week after she met a guy at the party, and started dating him, they’ve even got intimate from time to time. During that time i was working abroad and when i returned she asked to meet up. Told me she has feelings for me and missed me, so we got back together 2 times, we spent time greatly together even got intimate. After every time, she returned to him and after the second, they started the relationship, but got into an argument after a week, so she sent me snaps for 3 weeks, crying saying that she misses me. We started chatting again, she told me that she was alone all that time and she made a mistake, wanted to fix things, not rushing. I presume she thought that everything was over between them, it even seemed that she forgot about him. After a month that guy returned, they’ve met and we met in the same evening. She told me that after talking to him that everything is alright now between them, he is changing, that he loves her. at the same time telling me that she loves me and has feelings for me, but there is no spark between us everything between us is broken and what is broken cant be fixed, but she does not disapprove of the possibility that after 2-3 years we could get back together. One day later I got emotional and told her that I miss her and love her, and that no one will love and care for her like I did. She said that it was time to let go and that she fell in love with him and got attached to him. Before her this guy hooked up with 30 girls, and she knows it, even told me when we got back together during august that he is not a relationship type, he has red flags, and she knows them, but ignores them. The other guy doesn’t even know what happened during past 3 months. After a week of our meeting, she posted pictures on instagram, two days in a row of herself being all happy and pretty, started liking some relationship quotes etc. etc. 34 days has passed since our meeting and i am in no contact, feeling better right now . Thou i am still trying to make sense if its a rebound or not.