She checks in with him from time to time, and he suspects it's just because she feels obligated. Not that she should, of course. If there's anyone who should feel the need to do something about his blindness, it's Eridan, and they found what was left of that royal douche hours ago - he and Karkat had dragged her away before she could start in on her macabre pantomime of investigation.
But she hovers, and asks if he's doing ok, and she yells at Karkat when he neglects to warn them about stairs. She phrases it like that, too - "Karkat, you've got to tell us when we run into stairs! Do you want us to end up blind and crippled?" - although all three of them know that she can navigate far less stable terrain than stairs with perfect ease. She steadies him with a hand on his arm as they descend and ascend, and he can't help but notice that her hand stays a bit longer than it needs to once they reach level ground.
He tries to put it out of his mind. It's probably just his imagination. Losing his sight should make his other senses sharper, right? So it's natural that he'd be more aware of physical contact than he had been before. She probably doesn't mean anything by it, when her touch lingers in a way that sets his heart racing.
Anyway, one dead matesprit is ordinary bad luck. Plenty of trolls lose their first red loves like that, it's a natural consequence of growing up in a society that openly encourages homicide among preadolescents. Two dead flushed interests, though, and he has to start to wonder. Two dead girlfriends, and Paradox Space outright labeling him the Mage of Doom? He wouldn't have to believe in predestination to understand what the multiverse is trying to beat him over the head with, here.
No, best just not to make an issue of it. He's pretty sure that she and Karkat are flushed for each other, anyway. Well, part of the time. Sometimes they come across as pretty damn black. He wonders, sometimes, if he should try and give them a nudge toward red, but decides against it. Not because he's hoping that she'll free up that quadrant, he tells himself - if there's anyone left who can manage to work together with a kismesis to survive, it's those two, and while he's not willing to force the issue on the quadrant he's started to stumble blindly into, he isn't going to get caught in the exact opposite quadrant, either.
So he keeps up, and tries not to brood, because when he broods she gets worried and checks on him and that just drives him deeper into this troll disease called infatuation.