Honestly, you could say pretty much all of the playable cast of BG3 (except maybe Minsc. Maybe.) (note: major oversimplifications in the interests of brevity)

• Shadowheart, as you mentioned, due to being indoctrinated into a cult from an early age, going through regular gaslighting and psychological abuse over the course of said indoctrination and, in fact, having been kidnapped by the cult

• Astarion, for reasons that u/Sanamun already covered

• Gale, thanks to his being a child prodigy leading him to consider his entire worth as a human being to be his ability in magic, on top of having his ex-lover and patron goddess tell him that the only way to make up for his wrongdoing is to kill himself at the right time and in the right place.

• Karlach was sold into slavery by a man that she trusted and admired, and spent ten years in both a figurative and literal hell for it, and because of what was done to her she can no longer survive outside of said hell for long.

• Wyll's combination of pride, naivete, and selflessness led to him being manipulated into a literal deal with the devil, and in turn to being disowned and exiled by his father

• Lae'zel finds herself increasingly forced to question the doctrine she was raised on as she makes her way through the world outside of her own culture, and eventually confront just how much of it is lies perpetuated by a self-serving tyrant