Degrading and my partner

I get off so quickly from being degraded, especially by being called a slut. If I'm masturbating I cant imagine the degradation, I have to actually say it to myself and I cum within a few seconds. My partner know I like it... but he doesnt know how MUCH I like it. He'll say things like "you sound so slutty when you moan like that" and "you're daddy's little slut" and I like that, it has me whimpering the moment he says it, but then that's it. He says stuff like that once, maybe twice, three times if I'm super lucky and it drives me insane because I need more of it. Just last night I was getting close to finishing and I started to think about it, hoping he'd say it, and he pointed out that I was mumbling something. I dont know what to do because I cant tell him I want him to degrade me, I get too embarrassed too easily and any time I try I just end up going silent because the words get stuck in my throat.