SUBREDDIT: r/relationships
TITLE: My [21F] boyfriend [22M] needs me to do something extraordinary for him to know I love him and for me to earn his love.
POST: Long story short, been dating for a year, we've had a lot of problems and one day I was drunk and kissed a girl, I know it was wrong, it was cheating but according to me we were on a break. I know, do typical, but a day before he got mad at me and said we should stop talking for a while etcetera. Well, apparently I got it wrong and it was not a break. About a month later I broke up with  him because we were hurting each other so much, but then another month later we fixed things and went back together, by then he found out - I confessed about the kiss and he got mad and then he got madder because I broke up with him when he most needed me and I chose my own happiness over his and he keeps reminding me the fact that I cheated on him. I'm not saying it was OK or that I should be forgiven, but he does says he has forgiven me but he can't forget and I can only imagine us being 50 years old and him still telling me "no, you don't deserve that because you cheated on me" 

Anyway, he's been mad at me for pretty much everything and well I admit I fuck up very often and I don't give him the support he needs in these dark moments, but I'm trying really hard. He told me he needs me to do something extraordinary for him so that he'll forgive me and he'll believe me that I actually love me and so that he'll love me too and we can be happy, the thing is, I have no idea of what extraordinary thing I can do. I don't have a lot of money so I can't buy a lot of things, I'm thinking of sewing a jake the dog plushie, I've been leaving him notes, drawings and letter and I sang him a song today, but it hasn't been enough yet, I need something really big and amazing that will make him know that I truly love him despite my mistakes. Reddit, what can I do to show my love with an act?
TL;DR: 
I've been fucking up everything in my relationship and my boyfriend needs a reaffirmation of my love and I need to earn his love too in an extraordinary act of love. Yeah, like a Disney tale. What can I do?