In bed we were both reading and she turned over to me and said, "I'm not doing anything to betray your trust. Nothing. Trust me. And, I want to let you know that even though you annoy me every day (laughing), ILY very very much." with a sweet smile on her face. MY HEART LEPT A THOUSAND MILES. Weird to say it, but that's the BEST I've felt in months. My W never says much like that. I immidiately thanked her for her comment, said ILY back, and I gave her a kiss as she smiled.
Best way to respond:
(Smile) "Thank you. I wish I could believe that right now. Goodnight."
Regardless of the depth (or lack thereof) of your wife's EA, it's still way too early to fully trust her right now, especially to tell the truth.