Later…
Padmé decided to leave Anakin. Anakin started to choke Padmé using the force and that is when Obi-Wan's ship arrived.
Padmé's blurriness allowed her to see Obi-Wan standing before her.
"Anakin," Obi-Wan said. "You need to let Padmé go."
Anakin's suspicions about the Padmé-Obi-Wan affair were confirmed and he thought that the two were there to off him.
"Let Padmé go, Anakin," Obi-Wan repeated.
Anakin stabbed Obi-Wan with a lightsaber; however, Anakin' s good side took over. "The light side is dominant right now," Anakin said to Obi-Wan. "I don't know for how long. I'm going to stab you where you will have a fighting chance."
And so he did.