Caipirin you are so, so correct!
Writing as someone whose first name is Dorothy.... ComfortHer, think seriously about Dorothea. A Dorothea can be "Dottie" when she is little (until she is 4 or so), and then (before she is teased) it can be shortened to "Thea".
I emigrated as a child from the NL to Australia. Dorothy is a normal name in the NL and it is shortened to Dortje.
My Dutch nickname (Dortje) was considered unacceptable by the Australian primary school I attended. My teacher told me that Australian Dorothy's are always called "Dot".
This was swiftly changed to "Snot" and "Snottie" in the playground. The teachers didn't care and I have a strong, unpleasant childhood memory of the headmaster mocking me, calling me "Doffery" (which I still don't understand, but am sure it wasn't a compliment).
When I started university it was a relief to get away from this and introduce myself as "Dorothy".
Even now, in my 40s (Australian) people can't resist. It has changed to mild teasing ... "Oh, where are your red shoes?" (from Wizard of Oz). "Oh Dot and the Kangaroo!" (some stupid Australian book that I have never read). "Dorothy the Dinosaur!" (The Wiggles).
Dorothea is easier.