Why was Germany bitter about the treaty that ended WWI?

Germany was bitter after the war because they were forced to take all of the blame for the war, they weren't allowed have a military of their own in fact their military was and still is consist of American soldiers, also they lost a lot of land in due to the war, also being that they had to take blame for the faults of the war they were forced to pay us back for the damage that was caused.

The treaty was signed by Germany on June, 28, 1919 ... The terms which caused the most resentment in Germany were the loss of territory, the war guilt placed solely on Germany, the deliberate effacement of the German military and the demands of reparations.