You neglect that Sasuke is on a top secret mission tracking down a potentially greater threat than Kaguya, of which Sakura was present when he took said mission. And considering how much of a problem Kaguya was, coupled with the nature and secrecy of his mission, it's not like he can just drop in from time to time to check up on his family and stuff. Maybe fire off a hawk or two, just to let Sakura know he's alive and stuff, but not to visit. It's been made abundantly clear the people wouldn't be able to deal with another Kaguya attack.
Also, I might be mistaken, but I think Sarada's 10 at the present time, so Sasuke not seeing his child for over twelve years would be forgivable since that's not his child! [Insert NTR comments here]
Stockholm Syndrome... I do not think that word means what you think it means. Not to say that Sakura isn't stupid in love, but her basically rewriting her values to match his to make him a non-threat to her life is a stretch. As for Sasuke, let's face it; he was intentionally being an asshat because of his need to break off relations with everyone, as he viewed those bonds with friends and loves as things that hindered him, made him weak. Thanks, Itachi; thanks a lot.
It depends on how you view it, and I just don't see it that way.
Regardless of this so called special threat, you also have to take into account that for the last 10+ years, Sasuke has found literally nothing to progress this mission. Shin literally threw himself at Sasuke in return. So basically all of this is happening now, and not in the span of 10+ years. This is why him not being able to see his family is still inexcusable. I think it's quite obvious that the mission didn't progress that far, so during that entire time span he couldn't at least send a hawk to Sakura? Or at least text them or call, considering he has a cell phone???
Also, from the recent chapter, we've learned that Naruto and Sasuke became "rusty", meaning that they haven't had an all out battle for a long while. This further drives the point that no other villain has been that important enough for Sasuke to contact his family.
And if they're about to graduate from the academy then Sarada is not ten. More than likely she's twelve. This also alludes to how Naruto first began when Naruto was 12.
And yes, Sakura had a crush on Sasuke before he started to physically abuse her. But after his first killing attempt towards her, and the fact that she's fallen even harder for him since then, her feelings have become eligible enough to be considered as Stockholm Syndrome.