Flower, did he actually "ask her to sleep with him" or "ask her if she would sleep with him"? Notice the difference in verbage? If it was the latter, I would chalk it up to insecurity and needing to feel desirable. Unknown to most people, woman especially, men have the need to feel attractive too. Just how woman dress to go out with the girls, knowing damn well it is provocative, but no harm no foul. THe woman wants to feel hot, she wants to feel desired. COMPLETELY NORMAL! Especially in relationships where one partner is not as forthcomin with the compliments as they should be. BUt no matter how much you shower your mate with affection and "you look amazing" comments he/she will sometimes always want to know hat you aren't the only one and that he/she still "has it". My wife is this way. I tell her all the time she is hot, beautiful, cute, sexy, etc. but I understand that she still gets a kick or a rise out of a guy hitting on her at the bar, or a guy "eyef**king" her at the beach. It is just human nature. We are vain. We want to know we got it. So, if he asked in the latter terms, let it go. If it was the otherway, it is a whole different story. Hope I helped. Take care!
