The "I hate sand" scene is two very broken people trying to be normal.
Padme's a child queen who has given up any sense of a normal adolescence to be a politician that actually fights for the good of her people. she simply has no time to be a normal girl or young woman.
Anakin's never had a chance to grow to be a normal young man because his teenage years were stuck in essentially a monastery. He's had Padme on his mind the whole time, and I suspect in no small part because he was never allowed a normal teenage relationship with girls.
Throw them together and they clearly want each other but don't know how. Remember how awkward you were in high school trying to be cool and debonaire, but in looking back you can see just how awkward and pathetic you were? That's where Anakin is. He's trying to sound like he's an awesome guy but he's just fumbling the whole time. Padme knows it's wrong to get involved with him for many reasons, but he's got her moister than an oyster. But she's also fumbling because she has no life experience to fall back on. Even after he confesses to killing the sand people and she's thinking "I'm in love with a human time bomb" and even after the scene where they say they both know it's wrong and can't let it go on, she still says when they're being led into the arena to be executed that she loves him. She simply doesn't know how to say "no" and mean it because her background meant she didn't have a normal childhood.
They were both set up for failure by their lives. They were simply never going to have a "happily ever after" story because of her political life and his Jedi life. Once she got pregnant, Anakin's days as a Jedi were numbered. He couldn't have her and the Jedi and would never give her up.
The PT was very much a Greek tragedy just like the OT was very much the archtypical Hero's Journey.