I am an ex-Christian (the whole evangelical 9 yards) and this sounds horribly familiar. Something that you really enjoy, not 'sinful' as such but takes up a lot of your time and commitment: serious competition for the big G. So you pack it in, you've made a sacrifice, bit of kudos from your fellowship, but the warm glow won't take away the sick feeling that tells you you've made a mistake that's difficult to reverse.
I'm not going to try to convince you that Christianity is a crock, you need to find your own way on that one, but the at the end of your post says it all.