I mean zero offense with this, but every time I think of Mormon's, I think of an episode of South Park.
How do you handle people telling you that your religion is "made up?" I hold the view that all religions are the creation of man, but Mormons seem to get a lot of flack for it.
I've actually seen that particular episode of South Park (I don't usually watch the show, but somebody mentioned the "Mormon epsiode" so I had to check it out). The funny thing is, they did get some of the aspect's right, but most of it was totally wrong. For one thing, Joseph Smith didn't have a magic hat that he looked in to to translate the book of mormon.
We believe that God always calls prophets to lead His church on the Earth (like Moses, Abraham, etc.). After Christ was crucified and the apostasy, we believe that God took his true gospel from the Earth, leading to the dark ages, a time when there was very little advancement of men. In the 1800's the age of Enlightenment was in full swing, and most men were looking for the true church. At this time, we believe that God restored his gospel to the Earth, through the prophet Joseph Smith. So because God has always called prophets, it doesn't seem that strange to me that we would have a prophet nowdays, especially because we believe that God is unchanging.
So that's how I handle people telling me that my religion is made up. If it were made up, that would be because Joseph Smith was the biggest liar in the world, but keep in mind that he only had a third grade education and it would be very impressive if he were able to write a book over 500 pages long in about three months, that conforms to the same linguistic style of writing found in the bible, many of which were not discovered and studied until well after the Book of Mormon was published. So when people tell me that Joseph Smith made it up, I just find that baffling, personally.
But honestly, the only one that could ever prove that my (or any other religion for that matter) is true, is God himself. That's why we encourage people to read the Book of Mormon and then pray to know if it's true.
Sorry that was a little lengthy. I hope I answered you question!