"I am the Co-founder of a growing company" is fine. You really don't need to get hung up on this. Call her Queen Amidala if it'll let you get back to creating

"I am the Co-founder of a growing company" is fine. You really don't need to get hung up on this. Call her Queen Amidala if it'll let you get back to creating value. Sounds like you've got a well-balanced team, an idea you all believe in, everyone's happy with their shareholdings - move on!!