Ever have something happen that sets off a trigger you forgot about?

I was reminded of a situation over 8 years ago recently. It set off a response I hadn't been expecting, but I am not displeased with it. It has made me more cautious and stand offish, simply because the feelings of abandonment had been so strong.

Now I am treading lightly to prevent the old event to happen again.

Yes, this is vague on purpose. Sorry.