Gosh, I think it would be really hard to get your mojo back if your spouse was saying things like, "You wish," when you said FU. Sorry, but there's a problem there.
I don't blame you for feeling self-critical in front of this man, if he thinks that you desire him (he must think he's hot sh*t) and he desires you only when you're in a certain nightie (bet that's not really true, but that's the message he was sending).
You can either practice feeling sexy no matter what (in that nightie, knowing you're wearing it to enhance HIS LD response, not to really BE sexier) or you can wait for him to decide to treat you like you are sexy. Of course, my whole obsession would be to try and find out how frequently the man found me sexy, with or without nightie.
Did he ultimately feel turned on by you that time? What happened in the hours/days following the wearing of the nightie? Did you ultimately feel the sex was good? Did he? This might be a place to start talking. (He asked you to wear the nightie, did he then feel obligated to perform or did he actually feel you looked cute and sexy? I don't know how you can go on without knowing!)
If he felt obligated, then he needs to figure out why he asks you do to do something that doesn't work for either of you...
