I think the lore implications is that the Skywalker line extends before Anakin, because he got those genes from somewhere. In either case, it's a good point to bring up. It could even be a massive logical error to fit the story they wanted to tell.
if she was tapping into the dark side i could understand
Sorry to nerd out here, but I need to make a point of this.
It's not easier to become a Sith Lord than a Jedi Knight, since they're fundamentally the same thing. Anakin is a nice case-study, because I don't believe he was ever really a true Sith or Jedi until he had reached about Episode IV-level Vader.
Theoretically, the difference between Light and Dark is the ideology and application of your power. You still stem energy from the same source (the Well of Life or whatever the forget it's called), but you just apply it differently, for different goals.
True Dark Side characters don't just destroy everything and eat babies for fun. That would be like a "Jedi" who used their powers to be the best servant in an old person's retirement home. It's an inexperienced, immature worldview and that is why you hear a lot about the Jedi and Sith having giant libraries and philosophy classes all throughout the canon.
You are not a real Jedi or Sith until you understand the full extent of what the end goal is, and aim towards that. Until then, you're just some dude who has superpowers.
See, the Jedi and Sith are two big ancient groups want really just want the same thing; peace. But the Jedi mean to do it through diplomacy and the freedom of individuals to choose their fate (so long as it benefits rather than harms), while the Sith believe in crushing any opposition and imposing their rule for the benefit of all. There's a lot of juicy philosophical debate you can have (and
Knights of the Old Republic II is a game designed entirely as a criticism of both sides, so I highly recommend you read Scorchy's Let's Play for more details).
One more time: "Jedi" and "Sith" don't refer to people who have powers, they refer to the two ancient ideological groups whose members may or may not have powers and want to reach their own version of "peace".