Being stuck on the same person

How do you tell yourself to walk away from a relationship when your heart doesn't let you and how can you even look at the person you love and turn away and tell yourself it’s not worth it anymore? I personally can’t do that if I could I wouldn't still have a crush on a guy who I have liked for three years now. There is still a part of me that wants to believe he will leave his games and tell me how he truly feels about me. At the same time I know I can’t wait on him forever hanging on hope and faith. I just really wish letting go of things would be easier. I truly wish there is a really good reason why I met you and a reason that won’t leave me heart broken. I guess it’s true you can’t make someone love you no matter what you do. What’s funny is that even when we know that things are hopeless we try to think to ourselves that there’s a chance. I really don’t understand how our mind picks the person we want but I hope it knows what it’s doing and not just picking at random.