Writing a book takes effort. Getting published even more. There are literally hundreds of well-known authors who were rejected repeatedly before finally being published.
To name a few
Harry Potter by J K Rowlings was rejected
12 times.
A Time to Kill by John Grisham was rejected 16
times.
Lust for Life by Irving Stone was rejected 16
times.
Lord of the Flies by William Golding was
rejected 20 times.
Dune by Frank Herbert was rejected 20
times.
A Wrinkle in Time by Madeline L'Engle was rejected 26
times.
Gone With the Wind by Margaret Mitchell
was rejected 38 times.
Carrie by Stephen King was rejected 80
times,
The Chronicles of Narnia by C. S. Lewis, was rejected hundreds
of times.
Judy Blum had to wait 2 years before being
published.
Agatha Christie had to wait 4 years before being
published.
Alex Hailey had to wait 8 years before
being published.
Gertrude Stein had to wait 22 years before being
published.
In some instances, with the rejection slip the authors received comments which often were quite personal and highly uncomplimentary about the work submitted.
These days, when publishers are being overwhelmed by manuscripts, instead of receiving a written response, you may be told that if you don't hear anything within so many months, assume that your manuscript has not impressed.
Share your expectations and experiences in submitting your work.