renew myself again

so currently I'm doing a 21 day fast only vegies and fruits in order to redirect myself back onto the path. I have a bf and he has agreed to go with me to church he can't because his dad and they constantly have problems. I know what the bible says, " do not be yoked together with nonbelievers". Anywho that's not my point here, although we haven't had physically sex(because I want to wait till marriage) we have thought about it and talked about it and sadly as well we have sent some pictures which I horribly regret.... I know it's adultery in a way. but I want to start New because I feel my clothing is so dirty now and I'm ashamed from going far from God. so this is why I'm fasting. I really am ashamed and pray forgiveness..