Need advice

There’s this guy I’m seeing and he tells me he likes me but i don’t believe him. I think i May be suffering from low self eestem. I find him a lot more interesting then me. How do i overcome feeling like this? When he does nice stuff for me i feel surprised, when he tells me he cares i feel shocked? Like you actually genuinely do? I guess I’m used to liars so i assume he’s lying.