I would say that's not an unusual reaction when recalling a difficult time.

Similar to you my depression is thankfully in the past, I also find it hard to talk about. But as Hooligan says it's helpful to remember we are not in that moment any more, it is a memory we are reflecting on.

I prefer not to reflect on my unhappy memory too long, when talking about it with others I am brief, talk about the positive outcome and that I prefer to look forward than dwell on the past.