Bart doesn't talk about what happened to him. There's just too much that he can't think about, can't deal with. Jaime has tried to help him. Tried to convince him that repressing and ignoring the memories would just make it worse. Tried to convince him that Black Canary, or someone, could help.
Bart just smiles at him sadly, and shakes his head.
I'm worried about what could happen. He explained one day, after some bugging from Jaime. I don't want to cause the end of world by telling someone who shouldn't know.
So, Jaime does what he can. He hands Bart snacks when Bart forgets he doesn't need to ration food anymore. He holds Bart's hand when he won't stop shaking. He talks when Bart needs noise to focus on, and stays quiet when it's too much. And when Bart has a panic attack, or a nightmare, and can't look at Jaime without crying or panicking, Jaime forces himself not to take it personal.
Because he and Bart both know it's not him that the problem. It's not him or the suit or even Khaji Da; it's the Reach and what they did.
And it's not like Bart is the only one in their relationship who's screwed up.
Bart puts up with the murderous bug on Jaime's back, and the constant muttering to himself that scares other people. He holds Jaime and talks to him when Jaime feels like he can't control his own body. Bart doesn't give him crap for not being 'out' to his very religious family in Texas, or for being both Christian and bisexual, even if Bart himself doesn't fully understand religion. Bart doesn't even flinch away from a kiss or holding hands while Jaime is in the suit.
Bart doesn't talk about it, so Jaime has learned not to ask. He doesn't ask about the scars on Bart's back. Or about the time on a mission Bart put 15 stitches in his own torso without even flinching. He doesn't question when Bart doesn't know some common childhood thing, or when Bart knows something horrifying that a 13 year old should never have to learn.
But not everything Bart doesn't say is some awful secret.
There are some things he just can't describe; like his mom's smile or his brother's laugh. There are some things Bart prefers to say through actions; like how he feels for Jaime or how he treats his friends. And then there are things that Bart likes to keep to himself; like his drawings or how Jaime makes him feel.
There are many things Bart will never say, and those are the things Jaime understand the most.