what's the story with Shae and Aela? why were they separated? how did they feel when they reunited?
Here's one post that's got some good info on that... here's another. there might be others, buried in the archives somewhere? Unclear
both of those touch on their current feelings on the matter, but I'm not sure if I've talked about the backstory yet so here's a summery, and I'll work on writing up the official backstory doc...
They're sisters, five years apart, born on Nar Shaddaa
the sisters were picked up by an orphanage when Aela was five and Shae was two months old
eight years later, the sector they lived in became the battleground for two opposing gangs, and the orphanage was destroyed
the sisters escaped capture by either gang and ended up on the streets -- barely surviving, hiding from both of the gangs for fear of being enslaved (which, as Twi'lek girls, would NOT be good for them)
they managed to find shelter with an older nikto, Lue, who had found shelter near one of the power generators
still not a stable living situation, though -- they had to keep moving to avoid being caught, and Aela frequently had to venture out to find food and supplies (very dangerous)
one time, she gets caught by some of the lackeys and manages to convince them to take her as a minion, rather than a personal companion for their boss... this earns her the privilege of living in an actual shelter without being mugged or killed for not paying the gang's fees. She returns to Shae and Lue and tells them she found a safe place for them to stay. She does not tell them what she did to get that place.
Aela works as an enforcer for that gang for years. Puts up with a great deal of abuse, for Shae's sake. She tells Shae and Lue that she found a legit job somewhere and she's going to do that. Lue definitely suspects, but Shae only realizes a few years later and there's a whole argument about it... the result being that they make plans to stow away on a cargo ship once they save enough money to start over somewhere else.
Lue refuses to go. She's getting old, and she's worried if she tries to come with, she'll get them all captured. She'll take her chances here, just like she was doing before they found her... and she insists that they go through with the plan, so they can hopefully get to a better place
Trying to stow away goes wrong -- Shae ends up making it onto the ship and Aela is left behind. The ship is then attacked by pirates, who capture Shae and make off with most of the cargo... Aela doesn't realize this, and assumes Shae made it to the ship's destination. When she later tries to find Shae and isn't successful, she assumes the worst.
In reality, Shae managed to get recruited by the pirates. Eventually, after bouncing between a couple employers, she made off with enough credits to stay alive for a few months and went looking for Nok Drayan's treasure...
Meanwhile, Aela was sick of putting up with the gang's abuse, and she no longer had Shae's safety to worry about. She shot the gang leader and escaped, eventually becoming a vigilante of sorts striking against the particularly bad syndicates and mafia bosses and whatever. Ends up in the wrong place at the wrong time, messes up Ffeud's Intelligence operation by killing his target... but he's so impressed by her methods that he gives her the option of joining Intelligence rather than simply executing her.
And uh yeah. That's the rundown