Hunter Thompson Post 1 The Hobbit

I am reading The Hobbit by J. R. R. Tolkien. I am currently reading chapter VIII, "Spiders and Flies".
So far a strange wizard named Gandalf had gathered fourteen others(thirteen of them dwarves and one normal hobbit named Bilbo) to embark on a journey of a life time. They have left off to set course for ultimate riches while encountering many mystical creatures that only Tolkien himself could imagine. Some of them friendly, but many dangerous. Right now, after Gandalf being forced to leave the journey, Bilbo, and all thirteen dwarves press on into the enchanted forest. What awaits them on the other side, or within the forest for that matter, is still a mystery. So far this book is amazing and so captivating every time I pick it up, I have to force myself to stop so I can get other things done. I think it so easily draws readers in like me because no one else could possible think of a world so amazing and magical as J. R. R. Tolkien's Middle-Earth. I think the reason Tolkien wrote this is because his imagination was like no other. Even by todays standards, the world he has created is so awe-inspiring, just imagine reading it when it first came out in 1937. This could have easily been the reason why he wrote it in the first place. I think Tolkien wanted us to think that even the smallest people in world can overcome giant goals that stand in our path. This theme can easily be proven through my favorite character in the book, Mr. Bilbo Baggins. He is the most interesting to me because no one really thinks much of him in the beginning, but they soon come to see that he is capable of nearly anything. Bilbo has changed so much since the beginning. He used to just tag along and crouch in fear for every enemy that crossed their path. No he has saved every one of them from death at least once, if not more.
One interesting quote from the book reads, ""Do we really have to go through?" groaned the hobbit. "yes, you do!" said the wizard, "if you want to get to the other side. You must either go through or give up your quest. There are no safe paths in this part of the world. "" I love this quote because it shows that even though Bilbo wants to quit, he keeps pressing on, knowing that there is light at the end of the tunnel. The only thing I want to know is why did Gandalf have to leave the Dwarves and Bilbo halfway through the long journey?