I'm going to keep a secret.
Why do you want to keep it a secret?
I don't want to hurt feelings of a person who's really close to my heart
It's great that you're caring of other people, and it's generally good to keep secrets. Just be sure that your secret isn't something that can harm people by being kept in the dark. If you hold onto harmful secrets then you only draw out the amount of damage they can do.
Thanks. I'll keep that in mind.
Just keep in mind that some secrets are meant to not be told, while others are. It just depends upon the situation.