I'll add to this, gently. There can be some awkwardness around how others refer to the person in your life who died. "Ex" is definitely not it. Gently correct them.

Also, when I talk about that time or person in my life, depending how much I want to get it into it and the level of familiarity, I describe that person using one of:

- My late wife

- My wife, who passed away

- My wife at the time

- A family friend

- I know someone who...

If I'm trying to relate to something a relative stranger is telling me, I'll use one of the later versions unless I want to drop the (often unknown what to do with) bomb that I experienced such-and-such with my dead wife, too. Many people don't know how to handle that.