why do I feel like my friendship with you is like a relationship

I feel like I’m in a relationship when it comes to dealing with you. I’m crying because you stood me up then you finally text me and I’m happy again. Yet at the same time frustrated and debating if letting you back in is gonna be as simple as it sounds. WTF? WTF! WTF?! you’re my best friend or was I don’t really know where we stand.