How to not feel regret about your decision?
Be single or stay in the relationship that's not working out? It just doesn't feel like I made the right choice to break things off. I feel like I could have done more to save the relationship at that time but now it's kinda late to do that and I don't think I can move on or whether I even want to do that. I don't just miss being with her, I want her back but there's nothing I can do about it now and it makes me feel heartbroken because I can't imagine myself with anyone else. I don't think I can do a serious relationship like that with anyone else. I just feel so guilty for letting her go, for not doing more to fix things.
If my ex felt that way, I would have wanted nothing more than for her to reach out to me and tell me. If you love her, reach out. You were the one to break things off, so it is your responsibility to fix things if that is what you want. Don’t just give up, but be prepared that she might not want anything to do with you if you broke her heart. Honestly, if my ex reached out today, I would be willing to repair the relationship, but with established boundaries and going slow.