I've sometimes thought more in terms of "I can't follow her" more than "eww not her" ~~~
Meaning, there have been more women that I'd veto because of my own ego than because of something negative about them. I always try to recognize that it's my ego being challenged and not veto those women. Almost always -- they were really nice girls and I ended up liking them too.
In our case though -- it is a matter of complete trust and comfort with each other and ourselves which some days is stronger than others.