I would say to her.....Sorry you didn't like the flowers I put in the room during our(really just hers) vacation. She will say..no I really liked them. Then you say....Well I took your silence that you didn't like them. Just to throw a truth dart out there that a thank you would have been nice!!!
How about just telling the truth instead of saying the opposite of what you think and calling it a "truth" dart instead of an immature hint.
"I noticed you taking pics of the flowers. I'm glad you liked them, but it hurts me when you don't say thank you."
Or I don't appreciate it when you don't say thank you
Or I would appreciate it if you said thank you
Etc.
Breakaway's right, H4U -- those are better. I guess I'm a little too close to you, and get angry at how I see your wife treating you sometimes.