Ansel knows, I'm sure. Ame knows something is different, but she doesn't know what, never having experienced being in love. Silly is just Silly, totally oblivious to everything involving people and relationships.
On another note, Silly and Tazz were about as married as people on the street ever would get. Think of Silly as widowed, rather than just having lost a friend. Because think about it: They kept a house together, shared food together, started a family (albeit by adoption and not by actual blood) together. So... Yeah. Yay for premature serious relationships!