Of course other people feel this way, it's a normal part of the process. I've been at this point -- and beyond -- more than once in my dancing life. Sometimes it's just a natural part of the learning process, and sometimes it's a signal that it's time to re-evaluate what you are doing, with whom, and why.
Here's a little anecdote: one time a few years ago I said to my teacher "I think I've finally reached the point when most people just give up and quit." He just laughed at me good-naturedly and said "you've reached and passed that point so many times already you might as well just keep going." So I have, but along the way I've changed styles, coaches, partners, and my own reasons for dancing several times. I don't think there's anything wrong with this, either: dance is part of life, and as such is a growing process. Nothing is easy all the time, and things change all the time.
Good luck to you. Just think back to why you like to dance in the first place, and see if that's enough to keep you going.