You need time to heal
Dear Kristine:
Last week I learned that my twenty year old marriage is dead.
I learned this the worst possible way; my daughter told me her father confided that he's in love with his colleague.
My daughter is fourteen and was devastated, of course, by the news. To make matters worse, my husband insisted she not tell me, her mother.

It has killed her innocence -
How do I proceed? What do I do? I need help. I mean, real help. I mean, tell me how to put one foot in front of the next.
I am devastated. . .
Jane
- - - - - - - - -

How awful.
First, you need to assure your daughter that everything will be okay. Tell her you are sorry for her father's inappropriate behavior and promise her she will be able to rely upon you during the difficult days ahead.
Of course you must confront your husband with his outlandish behavior. When the facts are in the open, you will need to take steps to move him out of your home and begin a legal separation.
Your next conversation about these events should then be with an attorney.
After you secure your home, your financial base and your confidence, take some time to let the dust settle.
It may be hard to understand right now, but this horrific series of events might not be the end of your marriage.
Time. You need time to heal from this, and time to make sense out of what has happened.
Give yourself a six month separation from your husband. If, during that time, he asks for a divorce, move in that direction.
It is possible that either you or he might wish to seek professional help for your marriage and your family during the separation.
My advise to you is to take your time - consider your options as you mend from this series of events.
Marriage is a challenge; even in the best of circumstances. I will keep you and your little family in my prayers.