...It's so much more than just the war.
(- also it's kind of upsetting that Carissa doesn't feel that she can say no to sex, but he puts that aside for right now -)
The Yeerk mindreading only goes one direction; Ma'ar can't show her the entirety of who and what he is as easily, but he can still give her more than Mindspeech can convey to someone without the Gift themselves. He pushes across a blurred impression, made up of a thousand fragments.
The plains of the Clan Kiyam lands, grass withered, mud dried and cracked around what was left of the watering hole after months, years, of drought... A man's broken body. An infant's skull, crushed by the chief's club. A woman's screams, from inside the tent he was forbidden to enter.
They were decent people, who he grew up surrounded by. Not like him, and he never belonged, but...they never hurt him. It was a world where almost no one was evil and almost everything was broken.
Travelling through Predain, alone, terrified, confused all the time. Reading everyone's mind constantly, and most of them were decent people too - worth saving, though he didn't quite have that concept fully-formed yet at the time - but none of them were like him either.
Seeing Urtho's Tower for the first time, and the hope he felt, seeing a place that was less broken. Thinking that Urtho, too, understood, that Urtho was like him, that he wasn't alone.
The slow realization, smeared out across years, that no, Urtho didn't understand at all.
Going back to Predain, and how it never again felt like home, nowhere did, the Tower came closest but that almost hurt more.
Ma'ar has spent decades carving out just one corner of the world where slightly fewer things were broken, and he nearly lost all of it in a fiery cataclysm - and Leareth did, and then picked up the pieces and spent years, centuries, millennia working to fix everything, and sometimes he had allies, for a brief time, but in the end he was always alone.
Ma'ar is the same person, the same pattern, and he can see how he could be shaped that way, pared down by the passage of time and loneliness, into something optimized for that one goal. But he isn't that person yet.