If you look on the history of art you observe how the most popular forms trample the rest. The abstract expressionists destroyed figurative work for more than 30 years.
Despite all the types of rejection, the most important part is to keep on moving forward and to not give up. If things are getting bad, take a break and seek out people for their opinion on what you may do to improve your presentation. In the end, it is all a numbers game and it does become a lot easier. It stops becoming this big ordeal and is just part of the job.