Hey man,
that really sucks
.
The first thought i have is: quite saying that line to her
. Allthough it might have helped you a few times in the past, it really aint helping you now.
It seems to me that you need to say this line, because you think it will make her more horny. Its like you rely on that single line so you could actually just put it in her. Not good.
I have never seen you in action when you are 'messing around in bed' and therefor this is an educated guess, but i have this hunge that you arent really that good at 'messing around'. When i read your post, I feel like you dont have a clue if she is actually horny or not. When you pass the line, you are really asking if she wants you inside her. it should be the total opposite!
The last though i have is that you focus to much on your own pleasure and you totally forget that she wants some as well.
Lets wrap this up. When i happen to end up in bed with a woman, she is my plaything and i am hers. Sex really is something you do together. I am quite good at sex, but i totally suck when my partner just doesnt open up (figure of speech ofcourse, not literally). And by not opening up, i dont mean she doesnt want to have sex. I mean she cant let herself go, because of issues or whatever reason. Anyway, you get the point. Secondly, i also focus on her pleasure. I want to give her a series of raging orgams that will make her a gimp for a least a day or two. I want her to feel her sour muscles when she gets up and then smile, because she didnt get the sour feeling by going to the gym. So i ask you: what do you mean with: 'messing around in bed'? Rubbing her clit and suck her nipples? Not good enough. Your woman needs to sigh with every kiss and blossum by your touch. Your every move should show your lust and your desire and your every caress should make her want you more and more, in such a way that when you ask: do you want me inside you? you already know the answer! That is how it should be mate.
Also, asking: do you want me inside you? is not a bad line, but it is something you use to tease. Ofcourse she wants it (or so it should be) but you ask anyway. However, you should also convey more leadership. If you dont already, then start talking dirty to her. You are a man, a freaking caveman with style and you want to ravesh that body her. So you say things like: "I want to kiss you from you neck to breasts... to your... belly... to your.... tighs. I want to be inside you (see the difference with: do you want me inside you?). I want to fill you up, ballsdeep and fuck you hard. I want you to feel me inside you, to feel me sliding in your warm wet pussy, rockhard and filling every crack. Perhaps your pussy is too tight for me, i am not sure, but i am dying to try out." Stuff like that. She sucks your cock, but have you ever eaten her out? Have you ever brought her to verge of orgasm and then let it be, so she craves for your cock like a freaking alcoholic craves his booze? Perhaps that is where you should start.
By al means, i dont know how things are, i wasnt there. I could be wrong and i mean to insult. I hope it might help you out.
cheers and good luck!
CHAT