[so...he may or may not be falling for his nemesis' sidekick? is that what he just heard? because that's some The Earthmate's Quest-level shit right there, man]
Then I suppose this may be repeating what you already feel, but I would not rush anything. If she is interested in you and isn't outright indicating so, she may have her reasons for wanting to hold back, especially with a past such as the two of you share. You yourself have your understanding of the situation confused enough by that very past. Take time to work it through.
[what for basic decency?? and Responsibility but still]
Then I suppose this may be repeating what you already feel, but I would not rush anything. If she is interested in you and isn't outright indicating so, she may have her reasons for wanting to hold back, especially with a past such as the two of you share. You yourself have your understanding of the situation confused enough by that very past. Take time to work it through.