[HOWMANY]

I'm not sure I understand. Are you suggesting that she is colluding to get the pot HU with the button or is it that she just happens to be 3betting the small blind every time the button opens the pot?

If it is the former then leave. If the latter then just adjust your capping range or coldcalling range to adapt to her large range. I suggest you start by capping more often to find out if the button will fold for 2 more because this is very good for you if he will. If he calls the extra 2 almost always then I suggest calling 2 in the bb much more often than you normally would and playing poker postflop. If you are not suggesting that they are cheating then your question is really no different than "what do I do if the cutoff raises every time on my button?" or countless other "what if my opponent does this?" questions that can all be answered by expand/decrease your range to take advantage of them in the best way possible.