This is the Schitts Creek wisdom every writer needs. I just got the kindest literary agent rejection I’ve ever read and it actually motivated me to keep sending queries. My book’s not right for that agent but it is right for some agent. My quest continues to find them.
The only way your book finds its readers is if you keep believing in your story and keep striving to find the path for it. Literary history is full of rejection stories and authors who refused to give up on their work as the rejections piled up. Be one of them. Keep putting your best work out into the world.