Update: Girlfriend cheated but still wants to be together???

I (24 M) found out my girlfriend (25 F) was building an emotional affair with a coworker last year and I found out during thanksgiving. I felt angry, betrayed and hurt. She stated she wanted to continue a relationship with me. I was reluctant but decided to attempt a reconciliation with her after she begged. 1.5 months later and we broke up today lol. She ended her communication with her coworker but let me know she could not mentally get over him. So I stopped trying to fight for us. It was an easy break up on my end because the longer I stayed and tried to work things out with her, the more I observed of her negative qualities. I realized how difficult it is for her to communicate her needs and that she will not say anything unless I prompted her to. I also learned that she needs constant validation and attention to feel worthy and she confidently makes promises that she can't fulfill. On my end, staying in the relationship also showed me how I failed to be a good partner (in the past). I could have been more attentive, appreciative, and enthusiastic about her. It was becoming hard for me to stay and to keep trying.

However, observing our relationship dynamic helped me define traits that I'd want in a future partner... if I were to pursue a long term relationship again. I'd at least be looking for someone who can communicate their needs, having conflict resolution skills, fulfill their promises, feel comfortable with themselves, and can be upfront and direct.

During the last two months, I tried to work on myself to be a better partner... but I could tell she was not putting in the same amount of effort. While our relationship dragged on, I did learn come to some personal revelations:

1) I cannot look for love, validation, and acceptance from an outside person. I thought I had found a safe person who could provide me that. Instead I realized that those are things I can only get when I give it to myself. I cannot rely on someone else to feel like I belong in this world. That was the hardest but most valuable personal revelation. It allowed me to say that it's okay to continue my life without her and that I don't need another person to fill fulfilled in this life.

2) I cannot waste my energy feeling anxious about another person. I cannot control another person's behavior or feelings. I can't make sure that they love me, I can't guarantee that they will never cheat. I can only control my own behavior and feelings. I can only put that negative, restless energy into what I can control... my own personal growth and knowledge.

3) I am able to set enforceable boundaries. I have the ability to let people know what I am not uncomfortable with, and if they cannot respect my boundary, I know that I can and will walk away.

4) Love is fickle. Committed relationships shouldn't continue if two partners aren't able to continue to meet each others needs. There should be no shame ending a relationship if the mutual benefit is no longer there.

TLDR: My (24 M) relationship ended after my partner (25 F) was having an emotional affair with a coworker (27 M) and we failed to reconcile.