How to care about myself more than boyfriend?

bohemian

Relationships scare me. I’m kinda dating this guy and he’s good to me and we connect a lot, though sometimes our different upbringings cause miscommunication. I find myself either obsessing over how we won’t work cuz he doesnt fit me or I’m not good enough for him. Regardless my brain tells me a lot of lies and creates a lot of stress and unhappiness for me and invents negativity I don’t wanna bring to us.

How do I just not care and be myself like we both want me to be? How do I just let things go their course? How do I just be myself without caring what he or anyone thinks (and if I’m me and he doesn’t like me then thats fine we’ll just be friends)? How do I let go?