But what do you think the AP is seeing that is making him have such trust issues?
Well, having cheated once, she has work to do to convince she won't be a repeat offender.
(a) She almost certainly emotionally cheated on you with him before BD, (b) it almost certainly progressed to physical cheating in that hotel room, and (c) he probably suspects that the "for some reason" all her texts with you were erased is not going to be a reason he likes--e.g., her being dishonest with you about what she was up to with him, or her being dishonest with him about what she was up to with you.
