Yeah, I think different people think of any kind of interaction as significant. Sleeping naked in the same bed to me means absolutely nothing. Light open mouth kissing (what I saw at the end of part 1) was also basically nothing - no seriously sloppy tongue twisting going on. And she never reciprocated when he gave her orgasm-inducing backrubs, which isn't interacting with him in my mind. He's getting next to nothing out of the relationship at a physical level, as it's all emotional. That's why I used the words "any kind".
Personally - if I had the choice at the start of part 2 to turn Nana away as a romance/physical interest (i.e. give up on her) I would have done so. It's just too much of a one-sided affair, going glacially slow. When I see the MC and Nana start into a conversation now (in part 2), I simply skip the entire thing until another character enters. She just doesn't interest me anymore due to the stagnant progress. She's like the antithesis of Kitty Cat - forever repressed and reading zero (0) of the signs being given to her. Or if she sees them she must think she's 15 again and has all the time in the world to act on them (which she doesn't). Cat however is a handful of joy, openness, and pleasure. I simply can't get enough of interacting with her.
Just my .02, others will have theirs also.
I understand.
You want a 61 years old woman that NEVER experienced being in love, to feel desire, to believe she is desirable, to feel lust, moreover to feel lust for the boy she raised, that she loves with all her heart, but only as a grandson until now. That she overcomes the already extremely adverse circumstances of her life experience, but, also the years of conditioning of how "wrong" incest feelings are.
That she does it as easily as Catherine that was in love with the MC since before her puberty, that has never felt the conditioning against incest, and is pretty much over ready to loose her virginity with him for the last 10 years or more. And you want to compare them?
OK, you have the right to have whatever expectations you want. You are creating your own frustration, but, you have the right to do it. As long as you understand that it isn't anyone else's fault but your own.
You clearly didn't understood who Allison is and what her life has been, how her small steps are indeed gigantic and completely out of character, for the woman she learned she is all her life. You want that she is like the others, without any considerations for what makes her special and unique.
Now, you stopped reading her lines, refusing yourself the chance to understand, to appreciate how she's changing, evolving. For us, that play this for the process, for the trip, for the slow voyage and slow erosion of her barriers, you are making a mistake, but... in the end, this is a single player game, it's up to you how you want to play it. We'll read your complains, shake our heads and will sigh and facepalm, because you are, with your unreasonable expectations, creating your frustrations, and there's really nothing that we can do to help you.
It's your game to play, play it how you see fit. Complaining about what you refuse to understand is futile, we can't relate to your "problem", because for the rest of us that don't play that way, what you call a problem we call it a feature.
So, good luck. Enjoy the fruits of your labor.
Peace