I can relate, sort of. I used to get overly excited about girl prospects that tied up all my energy and then never panned out.
It’s not the most efficient way, maybe, but one thing that worked for me was to just observe myself as I went through each event. Eventually, I could catch myself before I got too wrapped around the axle. I learned to treat the whole thing as “window shopping,” so I started getting less agitated by a new prospect and had a progressively easier time letting go. It also helps to observe the balance of energy going in. How much effort are you putting out vs how much they are putting out. If you’re doing too much heavy lifting, then you need to pull back and see if they respond.
There’s also an option to dive into yourself, not in a selfish way, but to understand who is the one who needs all this attention or who is somehow incomplete without a guy. It’s a seductive thought—that a guy is going to rescue you somehow from yourself. I used to feel the same way about women, but once you realize who you are and once you turn that level of interest to yourself, you are bound to realize at some point just how limited that kind of thinking is.
Despite your beliefs at the moment, you are whole and free right now. You don’t need anything extra to be complete, because you already are complete. You don’t even have to learn a new way of thinking. All that’s needed is to drop false beliefs, such as the one you are holding onto in this question.