I think the most important thing in the beginning is that you take responsibility for what happened. How can you fully believe that you can attract someone, when you in the same minute believe that someone can interfere? It's not that you have done anything to her, it's that you had something going on in your vibration that caused it to happen. Sometimes, the vibrational cause is hard to find. But think about how you felt, when she interfered and then think about if you can remember having this feeling before. I can only speak for me, but when I atttracted situations I didn't understand at first (when I was like "whaaat? I never thought that THIS would happen") I always realized that I had this exact feelings before in a different context.

You didn't ask a specific question, so I don't really know how we can help you. But when you are new to LoA, you first have to understand that LoA isn't a quick fix. It's lot of mental work, you have to learn much new stuff and you will grow on your journey. Don't expect him to be back tomorrow, don't expect him to be back next month. Sure, it can happen that quickly and nothing is wrong with positive expectations, but most people feel the lack of their person even stronger, if they don't show up in the expected time and that delays the manifestation further.