In 1964, Justice Stewart was trying to figure out how to legally define "obscenity" so that it could be accurately labeled in motion picture ratings. He famously said (paraphrasing) "I don't how to define it, but I know it when I see it". Trying to sort out the mess of misinformation in a WS's head and heart can be a little like that. As noted above, WS's will typically lie (to themselves before they even get to you) in order to protect themselves from feeling worse about themselves than they already do. Since words don't matter, actions are your best indicator.
I am a WS in year 5 of R. I don't think there is a way to tell if a WS is "ready" for R, but I think the appropriate question is if they are "capable" of R. In order to be capable of R, the WS is going to have to do a lot of hard work on themselves. They need to figure out why they allowed themselves to make the choices they did. They have to figure out what about themselves brought them to a point of lacking so much self-respect, integrity and empathy that they were willing to kick their spouse to the curb, throw their own dignity out the window, destroy the lives of those around them and how they devolved into the liars and betrayers they became. In short, they need to become "safer" people, safer to both their spouses and themselves. The general wisdom on SI says that it takes 2-5 years of work, both independently and together, to even get to a point where enough healing has been able to take place to where R can really begin. And that's assuming the work that needed to be done, was done in that time.
Here are a few things to watch for:
* Does your WS express empathy for you at all? Can they respond to your hurt feelings with care and understanding, or do they get defensive and selfish instead?
* Are they able to be sacrificial? That is, can they put your needs before/above their own? For example, if you ask for time apart, do they say, "Ok, whatever you need" or do they get angry and blame you for punishing them?
* Can they "own" who they are and what they did? When you bring up the affair, do they discuss it with you and ask about your feelings? Or do they devolve into shame, defiance and denial?
* Are they doing the work? Are they going to IC/MC, support groups, SI, anything at all? When they do, do you see changes, do they express revelations about their progress? Or do they refuse to make the effort to change?
* Are they genuine? Are they doing this work because they love you and respect themselves and want better in their lives? Or are they just scared of being alone or unable to live without praise from another?
It took me several years to get "out of the fog" and back to a point where empathy could return. During the first few years, I just couldn't get there. I remained defensive, pointed blame at my spouse instead, devolved into a shame spiral, and in general, made things worse for my wife simply by being incapable of seeing anyone else's pain or lives other than my own. To her, my wayward thinking made it feel as if the affair was still occurring emotionally. I could not "see her" and so she did not feel she mattered at all to me. We were "in R" but I wasn't really capable of it at the time. I was saying the right things, and even doing some right things, but at the end of the day, they still felt saccharine to her because I was doing them from a standpoint of my own desperation. I lacked the actual empathy and self-respect, and that, you cannot fake. When my wife started to see someone who could see themselves, and see her back, then things changed. She knew it when she saw it. Until that happened, she chose to "detach" and 180 and take care of herself, which is what she needed to do in order to protect herself while I figured my own shit out.
I am not a BS so I will not offer too much advice in that department other than this... you are early in this process. You don't have to make any R or D decisions right now (unless you want to). You can wait, and watch, and heal on your own time and terms, and see how things progress, for both of you. Who knows, your WS might do "everything right" and change to become the warmest, genuine and safe person ever... that still might not be enough to enable you to want to repair the relationship. You have to figure out what is right for you, what you need, what you want, and what you are willing to do, or not do, to get there. Rather than R or D, choose to just get through today intact, and then re-evaluate tomorrow. Rinse and repeat. So heal yourself first. Then worry about the relationship.