Princess Diana was actually why I sort of shrank away from it, and recommended Diane;also(and this doesn't help you!) I had a childhood friend named
Diane, I liked her very much.
As you're uneasy about
Deanna, best to speak up now;there are so many other names.
Since you've just now found out the sex of the baby, I'm guessing you are still quite early in your pregnancy.So you do have time to take a decision you'll both be happy with.
You might even want to move away from the "D" names, and try some other possibilities.