What you can do is ask her
why she's leaving and what you could do to make her want
to stay. Is there something in you or the way you
treat her that makes her unhappy that you could work on
in personal counseling? Would she go to marriage
counseling with you?
You could offer to work on
things and ask her to give you and the marriage six months.
Six months to turn things around for the two of you.
Six months to try to keep the family in tact - for the
kids if nothing else. Six months without her seeing
or talking to this other man out of respect for you and
your marriage and your kids.
Unfortunately, if she refuses
to do this then you need to respect her decision, wrong
and painful as it is. She alone is responsible for
and in control of her choices. The hard truth is that
it takes two to make a good marriage, but only one to
break it apart.
If she has an affair with
this man then out of self-respect you need to consider
asking her to leave your home. It’s not fair to you to
have her in such close proximity to you while she’s continually
hurting you. Every day you’d feel kicked in the gut again.
Furthermore, staying in the
home while having an affair would rescue her from the
consequences of her affair. She’d get to keep her home
and her family in tact. She’d have you right there waiting
for her and wanting her. And she could keep her affair
a secret from everyone who knows her. It’d be like her
affair didn't cost her anything! This protects her from
broken relationships, guilt, explaining her behavior to
others, and relocation hassles.
If indeed she leaves you for
this other man then make sure that you still continue
counseling. In that case you’d need help for yourself
to deal with the pain and adjustment of a pending divorce.
You’d need to go through a healing process and to learn
whatever you could from this.
You also expressed concern
about what you're teaching your sons if you let her leave.
I'm more concerned about what you're wife is teaching
them! I gather that you are teaching them faithfulness
to a spouse, dedication to trying to make a marriage work,
how to have Christian faith in difficult times, how to
deal with injustice and pain with honesty and courage,
and that no matter what you love them.
I'd encourage you to talk
with them about what's going on. Of course, don't
slander your wife even though she may deserve it.
But do ask them how they feel about the true state of
the marriage and work to draw them out and listen to their
feelings. And do make it clear to them that she
is the one who wants to leave and explain to them what
you've been doing to deal with this and to try to save
the marriage.