I cheated on my husband and now he keeps on fighting with me

When I first met my husband I was 17 and he was 18. Now I am 23 and he is 24 and we are married since October 2016. I cheated on my husband who was my boyfriend at the time back in 2011 when I was a junior in high school...So a month into our relationship I was stupid fooling  around with my ex on the low because I still had feelings for him but he also had a girlfriend too and our 2 year relationship was a mess. I still feel so guilty of it till today. My husband knows about it because someone told him. The issue here is I don't know how to make it up to him. He mentions about it often when he's mad and I live with this guilt every single day of my life. I have MAJOR depression and anxiety and sometimes for my actions I thinkthe only solution is to end my life but I always think twice about it because I'm religious and there are consequences when doing that. Although I suffer so much, I've always been an optimistic person. I always pray for the best and I truly believe things happen for a reason and everything is in Gods hands. I'm writing here because this incident happened 6 years ago but my husband keeps mentioning it and I cannot live with the guilt and sadness anymore. I suffer enough from depression itself. Anyone have idea how I can make it up to him? I love him so much and I want him to forget about it..... Nobody is perfect and sometimes we slip. I was a stupid 17 year old. What I've done then, I would never do now at 23 and married.