In-law wants to protect her investment with engaged couple
Your future mother-in-law might actually be a great asset to you, if you can listen and learn from her without feeling stomped on. If you don't want her involved in your finances, do not accept money from her -- and pay her back for this down payment as soon as possible.
Like every partnering couple, you and your wife are going to have to work hard to reconfigure your family structure. You two should be inside your (virtual) "house," with your parents, siblings and others just outside the door. In order to be let in, they must wait to be invited.
Your future mother-in-law poisoned the well somewhat by openly expressing her lack of faith in the staying power of your marriage. Your most positive response would be to prove her wrong.
Dear Amy: How do I tell my young-adult children that their father and I are divorcing after 43 years of marriage? One of them will be getting married next year, which makes this harder for me.
This is their father's doing and decision. I'm not sure I can present a united front.
-- Emotionally Overloaded
Dear Overloaded: First of all, I am very sorry. Forty-three years is a lifetime to be with someone.
Shock is going to be your early reaction to this news, and so my first counsel is for you to give yourself some additional time (two weeks or longer) to walk around inside your new reality before disclosing it to your kids.
There is little reason for you and your husband to present a "united front" to your adult children. United fronts are what functional parents of young kids bravely commit to when explaining their breakup, to lessen the emotional fallout and confusion.
You should make a commitment to feel your own feelings. This can actually be challenging for devoted spouses and parents like you. A confidant, friend, sibling or professional counselor can help.