I've posted a lot on this forum and everyone has given me such great advice with my query letters, so thank you to all! I wanted to post an update to say that I've received three full requests this past week!! I am beyond excited.
I spent ten years writing my first book and two years querying it, with no success. I fought against others' suggestions to start something new, until I met a writer in early 2020 who convinced me to start from scratch, so I did. I finished my second book in about nine months and I have been querying for about two months now, and already I have more positive feedback than I ever did those first twelve years.
There is hope. Keep writing, keep believing.