The downside to being connected to the Force is that Obi-Wan is, for better or worse, more empathetic than others. He used to have to guard himself against it unless he needed an edge during negotiations, but fighting droids meant he couldn't feel his enemies emotions, and feeling his troops own emotions could be helpful. Living in an isolated area meant letting his senses stretch out, having an early indication of anyone approaching. In short, Obi-Wan hasn't had to guard his senses in a long time, and he naturally, subconsciously has been picking up Padmé's emotions since he arrived.

Now, he can feel that burgeoning hope, as if a flower is opening inside him as well, and he presses forward, gently deepening the kiss, seeking more. Offering himself, whatever it is she's seeking.