And you want her to kiss your children with that mouth?
just kidding
That is a toughie. Some girls will do it and some won't. Most girls I have met will do it, a couple actually like it, but some don't want to do it at all. It was no big deal when I was younger, for some reason I could never get off with a blow job. So I didn't care if a girl did it or not. One time a girl even told me to spank her because she was a bad girl because she couldn't get me to nut in her mouth. I miss that girl sometimes.
When I got into my early twenties I guess I could relax enough because it started working for me. And then I really liked it and wanted every girl I slept with to do it. In that department my wife is willing and eager. She asks to finish me off that way nearly every time we have sex. She came to me that way so I had no problems or need to talk her in to anything.
I imagine though, if you found sucking dick revolting, it would be a difficult thing to do. I don't know how you make someone like something that turns their stomach. Getting your package as clean as possible is a must. She probably hates the smell of sweaty balls. I once read an article many years ago in Playboy that you could make your cum taste better by not eating things like shell fish or garlic ahead of time. They suggested some mixture of egg-nog, honey and other ingredients I can't remember that supposedly sweeten the taste. I don't know if that works, my wife called it holiday flavor! Your wife may hate the taste of cum so that if you ever did get a blow job from her you may need to pull out before you cum if you ever hope to get another.
Again when it comes to all the wonderful emotional and physical feeling of sex it is difficult to bring something in that a participant feels is disgusting and then hope to maintain all of those wonderful squishy feelings for the rest of the session. Imagine if your wife really really got excited about and wanted to stick large broom handles up your ass. Maybe you don't like anything up your ass especially a broom. But she really likes it and bothers you about it all the time. She brings it up before sex after sex making you feel sexually inadequate in regards to her. She asks all her friends what to do. She is wondering, "should I leave him?" Would you then break down and start doing what it is she wants you to do?