Should have known better

In the beginning of Act V, Beatrice is upset because Diaphanta has not returned yet from her night with Alsemero. She become impatient, and suspicious. Well I think she deserves to go through the suspense because it serves her right to trust Diaphanta. De Flores said it well, "Sure the devil hath sowed his itch within her. Who'd trust a waiting-woman?" (V.i.16-17). My thoughts exactly. Beatrice should have recognized Diaphanta's excitement and willingness to switching places as a clue to what might happen. I actually see this as a little humourous. Beatrice is trying to save her marriage, so she has to trick her husband and have the maid sleep with him so he thinks she is a virgin, and then the maid actually turns out to enjoy it and stays much longer than needed. That's hilarious.