Mikveh night conflict

We recommend preparing for mikveh before the affair.  That would significantly cut down on time spent at the mikveh, as would going to the mikveh closest to the affair.  

You might even be able to immerse in the middle of the affair and come back.  In that case, or if immersing at the end, you would take care not to wear any makeup that would be difficult to remove and not to eat meat at the affair.  (If it is a seudat mitzvah, such as a wedding, you could eat meat, so long as you take great care not to get meat caught in your teeth and to clean them well at the mikveh.)  At the mikveh, you would take a quick shower, comb your hair, remove jewelry, clean your teeth if you ate, and inspect your body in the mirror. 

Another option is to make arrangements with the mikveh to come later than the usual hours. Most mikvaot are willing to do this, sometimes for a fee.

If no arrangement works out, and your husband agrees, then you may delay immersion to the following night.

Please feel free to write back with any further questions.