Do not trust anyone. Including your relationships and spouse.

Make three lists of items - things you will want for yourself rest of the life, things you need to live, and things you want to invest for the time after you. Examples for each list: a good house in a good place, a set of low risk investments that will give you 250k p.a. perpetually, invest in a durable enterprise that will outlast you.

Then go about living as if nothing had happened.

When it comes to investment, choose boring non-exclusivist models. Aka. avoid maddoxes.