He's older, he's not your boyfriend, never has been, he's, apparently, closer to "adulthood" than you are... yet... your are insulting yourself, turning yourself inside out on his behalf, wondering how you can prove yourself worthy, be forgiven for not being perfect..... I want to scream! He sounds HORRIBLE FOR YOU. I've no idea if he's a perfect human being or not (though I've yet met a perfect person) but for you to feel this badly about yourself? Makes me think he's HORRIBLE FOR YOU.
Please rethink all of this. Love yourself. That's the key. Love YOU.