He watched Padmé for a few seconds after she asked about his attending their wedding, all manner of thoughts racing through his mind. They were more than familiar to him, though, given the amount of meditating he had done since he had arrived at the castle. As a Jedi, he should not agree to Anakin's marriage at all. It went against everything he had ever been taught, every tenet of his beliefs and his creed. It had led to Anakin's fall and Padmé's death, it had indirectly caused the almost-total destruction of the Jedi Order.
And yet...
And yet, it meant that Luke and Leia were born. It meant that, if Luke's history was Obi-Wan's future, the Jedi would be reborn and all would be well. If he was to follow the will of the Force, then Anakin and Padmé's marriage had to take place, no matter the thoughts of the Council on the matter, and they clearly forbade such things. Master Mundi had only managed to get married because his race was in danger of dying out and it was his duty to do so. This marriage was a love-match instead of duty and so it was against the orders of the Council, yet was clearly the will of the Force.
Obi-Wan had struggled with this dichotomy for many meditation sessions, but now that he was faced with Padmé, it came down to one simple question. Did he want his best friend to be happy? And he found that he did.