Tell her.
Cheating at all is the worst breach of trust in a relationship. If she’s as conservative as you say, she’ll probably get mad and hopefully leave you. I have absolutely no sympathy for cheaters -with the exclusion of very extreme circumstances, of which you are not apart of. You were being stupid, shouldn’t have been drinking or doing whatever it was you were -neither are real excuses.
I’ve been cheated on enough in the past to think if it happens once, it’ll never happen again. It’s a naive thought -one perhaps your girlfriend will have. Nowadays if someone cheats, I leave immediately -no questions asked. Unless you were in an open relationship or whatever, it’s not okay -and from how you’re acting, there’s a 100% it isn’t open. Be a man and face the consequences of making bad decisions.
