I think I've gone too far with catfishing
Why do you think you went too far?
I catfished a completely different person out of boredom, he considers me his girlfriend and we even had cyber sex.
Catfishing a person into believing you are someone you aren't can really damage them long term. They may never trust someone again because of what you did. Talk to them, be honest and apologize.
I can never do that, and it's in the past now so I don't see a point in bringing up those parts.
Don't you want to have a clear conscience? You were manipulating the feelings and lying to someone else and they were genuinely in love, I believe it's best to break that instead of leading them on some more. Being truthful can take you very far in life!