I’m sorry to hear that — preparing for something you really want and not getting it is really hard to deal with.
The rational advice is easy to give: stick to your process, get feedback if possible so you can revise, and keep applying to more jobs.
The emotional advice is harder to give.
Basically, you want to design part of your process that will prop up your motivation. Slowing down or quitting doesn’t help you get a job.
Some people go to an extreme volume game. Then they expect to get turned down a lot and no single rejection hurts that much. (I still find this to be emotionally brutal).
Other people flip to more of a How to Win Friends and Influence People model. They try to offer lots of value. Speak at meetups, write blog posts, make connections, offer help large and small. Then after those things are done, say “I’m looking for X type of job — if you know of any openings could you let me know?” This method is emotionally healthy because helping other people feels good.