In the event of an affair coming to light, it is in your best interest to be honest. If you try to omit or alter facts to minimize the damage on your partner, and when they later discover the new facts, they will feel they are being hurt all over again. So, the act transgression is an injury, and each lie they subsequently discover will be a fresh, new cut.
When an affair comes to light, your partner is in a state of hurt and shock: what is real and what is not. They thought things were one way, and now they discover that things are actually a different way. If new facts keep coming out, each time they need to re-adjust to what is and isn’t real. It will be hard to start repair work on moving grounds.
Other Tips
Your partner will feel hurt and angry and betrayed and a bunch of other complex emotions for a very long time. Know that every time you sit there and take responsibility, listen and empathize, you are contributing to their healing.
There will be better days and really awful days, like a roller-coaster. That’s the process. Stay the course and don’t despair.
Give advanced notice to extended absences (e.g., long meetings, travels). Your partner might want evidence as proof; look at that request as signs that they have not given up.
Be mindful of white lies and omissions. Even if they are not related to the original affair, they will send shockwaves through your partner’s nervous system. It opens up the question of “what else are you hiding?”