@PM - Yeah, I don't need to see anything. I just want her to be completely open about it.
@Gabby - she is still refusing to stop communicating with him until she can "completely break things off", so your suspicions may be right. She said she will give me her phone pass-code to see all the texts, and she is not texting anything "romantic" - she wants to be fair and not make him wonder what's going on because he isn't at fault. She said she is texting him about his friend fixing her car, and of course she has to text to schedule a time to talk. I told her she'd have to get her car fixed somewhere else because she is not going to see him to do that. Once she talks to him and tells him we're reconciling, then there will be no further contact.
At this point, I've just put a safe distance because you're right, it is a little fishy. I've told her how I feel, and that hasn't changed, so no need to harp on it.