I like Martha, or at least the idea of her. I just didn't like the character assassination that RTD performed on her throughout series 3.
I thought it was pretty clear from the start that Martha had the hots for him, so I never saw any inconsistency there. And while I agree it would have been better if they had never gone there in the first
place, I thought Freema herself still had more than enough personality and charm to make up for it.
It was only later, when they tried to make her some kind of badass UNIT agent, that I thought the character felt really off.