Just one difference there, Dooku was the enemy who he didn't like(and he knew it was wrong to kill him) whereas Padme was someone he loved. Plus already Anakin was emotionally unstable in EP 1, even Yoda knows this...plus the fact he also lost his mother in EP 2 doesn't really help him. If he had been taken in as an infant, he would have better control over his emotions.
I agree about him being unstable. The fact that he is this emotional train wreck is where i just stop liking him.
I imagine if the war ended and he was home all the time with padme; she would divorce him.
Why she want to live with guy like that, when she could have kit fisto.