I wouldn't say Dohu is lying to himself. That requires self awareness, which Dohu doesn't have due to him being born that way. Dohu may be perceptive at others, but absolutely clumsy when it comes to his own feelings. Even now, he is still clueless that his mood and well being are being dictated by Juheon's existence.
Yes I don't mean lying in the traditional sense where he's aware of it & actively deceiving himself, but more like he's slowly becoming more aware of his own self and feelings. He's almost breaking out of the mold society made of him as someone unfeeling and discovering that not all the expectations about him are correct.

juheon’s fears are valid, and i would never blame him for hesitating around dohu. he’s spent most of his life being deceived, including by Dohu himself, so it makes sense that trust doesn’t come easily to him. he’s used to being alone, and because of that, he spends so much time stuck in his own head.
what makes dohu’s appearance now important isn’t their history, but the way he communicates now. he say things at face value, without layering them in hidden meanings or social performance. for someone like Juheon, who is constantly searching between the lines, that kind of honesty can feel overwhelming, but it can make him confront the shit he’s running away from.