I'm not clear what your position is at this company or if this a business you own, but I assume that (since you have can include someone on the trip who had nothing to do with the project) that you're in some high-level position of authority.
The reason that I bring this up is that, not only would it have been unprofessional to kick this woman off the trip, it could've been seen (at least in the US) as hindering her professional development/ability to advance because she's a woman. You also need to take into account that being rude with her (ie, telling her to ride with someone else because she said your driving made her nervous) or refusing to travel with her could be construed the same way. You really need to be careful.
I know at my company, there was a discussion about whether we wanted to include women in a client-facing role in a company that was based in the Middle East and the response from HR and our legal team was that we couldn't just exclude women from important accounts because the client might be bigoted against women.
Now as for your main question, even if you had never cheated on your wife, you still need to be mindful of your boundaries and avoid situations that might compromise you. But the reality is that you can't outright avoid half of the population for the rest of your life. If your wife doesn't feel secure enough in your relationship 10 years post Dday, then that's a whole other problem.
More importantly, you shouldn't put rules in place for yourself or make promises to your wife that are unrealistic. That's just setting yourself up for failure.
How does your wife feel about this?
[This message edited by BluerThanBlue at 3:43 PM, Friday, June 20th]
BW, 40s
Divorced WH in 2015; now happily remarried
I edit my comments a lot for spelling, grammar, typos, etc.