Yeah...logic is seriously screwed up here. I feel like I'm reading Alice in Wonderland or something...
Anyway!
Why didn't Anakin make a red lightsaber? - Better question: Why bother making another lightsaber when he's already got one?
Why didn't Sidious know Obi-Wan was going to Mustafar? - He didn't?
Why didn't Yoda stick around and fight the Clones and Sidious? - Because he had lost his lightsaber.
Why didn't Padme want to live for her children? - Because Anakin had mentally killed her. Her heart was broken, and she had not fallen madly in love with her children...
Why didn't Obi-Wan just cut off Anakin's head? - He couldn't.
Why didn't Bail help Jett Zukassa? - Better question: How is Bail going to fight through an army of clone troopers with a pistol?
Why didn't Agen Kolar block Sidious' first thrust? - Because Agen Kolar was a minor Jedi character and needed to be killed to show Palpatine's skill with a lightsaber.