Harry was best friends with Tom.Seven didn't have any respect for Harry. She treated him like a particularly dim child most of the time. More than that, Harry had no respect for himself, while Seven had very high regard for herself. Someone as confident as Seven paired with someone as unsure as Harry is a recipe for an imbalanced relationship.
Yes, but we're speculating here, right? In an ideal world, on an ideal VOY, Harry would have grown up. At the end of seven years, he wouldn't have been the same kid that he was at the beginning. And if that had happened, he might have grown into a relationship.
Of course, TPTB didn't allow him to grow up, which is a shame for more reasons than this one, but if they had...well, no telling what we would have ended up with.
Besides, I agree with Teya that Seven wasn't really that confident. She was intellectually confident, yes, but emotionally, she was very unsure of herself, very vulnerable. That robotic mask of hers really was a mask, as Teya put it. Honestly, sometimes I just wanted to give her a hug - which she wouldn't have known how to react to. That's how emotionally unsure she was.
I agree, she was emotionally unsure. But the fact that she continually pretended not to be would be intimidating to someone like Harry, wouldn't it? Ater all, he's no mind reader.
Tom wasn't emotionally mature himself & Harry just let it roll off his back. I don't think he would treat Seven much differently. Harry did have a pretty thick skin for this type of thing.